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Geologic Map of the Known Worldby Isabelle Sarikhan
This geologic map is a general overview of the Known World. This map covers only bedrock geology; omitting 'quaternary' aged deposits (mostly glacially and modern derived sediments, ages 5 mya to present on the Mystara timescale).
The Geologic Map of the Known World was compiled chiefly from descriptions in the Gazetteer series (Gaz. 1 to 14), Dawn of the Emperors Boxed Set, Champion of Mystara Explorer's Manual and the Poor Wizard's Almanac and Book of Facts (AC1010 to AC1013, including Joshuan's Almanac and Book of Facts). The author corrected discrepancies, where they occurred. In areas where no information was available, surrounding geology was used to extrapolate the local geology.
Map Designs and Standards
The Geologic Map of the Known World displays geologic units chiefly by age and lithology, not by geologic formations and terranes. The age of metamorphic units is the protolith age, not the age of metamorphism.
Unit symbols consist of uppercase letters denoting age, with the youngest first, followed by lowercase letters, showing first the general lithology subdivision, then detailed lithologic information. For example, KYDAit is the symbol for Kavashan-Darekhtan intrusive tonalite. The most common symbols are 'i' for intrusive (igneous), 's' for sedimentary, 'm' for metamorphic, and 'v' for volcanic. If the unit is composed of one rock source, it will just bare the symbol of that rock unit. For example, a pure quartzite unit will be labelled 'qt'.
Because at this scale of map units are age lithologic units, formations consisting of diverse types or ages of rocks are separated into their component of lithologies and/or ages and included in more than one map unit.
Recent to Mardan
This formation is composed of recent volcanic deposits. Most commonly, deposits of ash fall are interlayered with pyroclastic flows, lahar deposits, and lava flows. These volcanoes periodically erupt, adding layers of ash and lava. In the Ierendi Islands, volcanoes erupt effusively with mafic magma. Basaltic flows are common and eruptions can be active for numerous years. Some of these volcanoes, rarely, produce lava flows of pure metal, such as electrum, gold, and copper.
Yakhan - Sedaran
This formation is composed of intrusive rock of periodic emplacement from Parendan to Yakhan age, primarily granite, with granodiorite, quartz diorite and tonalite, locally known as the Altan Tepes batholith. Felsic rocks (granites) are dominant in the northern extent (i.e. Kingdom of Rockhome) of the batholith, grading into diorite to the south (Empire of Thyatis). The Altan Tepes batholith, during its intrusion into the country rock, brought high amounts of metallic minerals, located within contact margins, metasweat (primarily quartz) veins and breccia pipes. Many of these veins have been supergene enriched (weathered to the water table). Free-mill gold in the County of Halathius (Empire of Thyatis) is primarily from metasweat veins and breccia pipes. Porphyry deposits within the Altan Tepes range in the Kingdom of Karameikos has shown gold, silver and copper. However, most of this is in sulphide form. Metasweat veins in the Kingdom of Rockhome are rich in silver and gold and are primarily sulphide free. Porphyry deposits within the Kingdom of Rockhome are located in the far eastern and western extents of the batholith, one near the ruins of Jhyrrad, the other in the Makkres Mountains, between the headwaters of the Makkres River and the Klintest River.
Batholith contacts with limestone deposits have created large skarn deposits. These skarns often contain high concentrations of metallic minerals, primarily galena and copper sulphides, with the occasional tin. Often, rivers running through these deposits create good placer deposits downstream. Large vugs produce beautiful quartz crystals, often with pyrite and haematite crystals. A small mine near Landersfjord (Vestland) have produced numerous sceptred amethyst crystals. Jacinth of good colour (deep purple, violet, and pink) is located north of Fort Hobart (Republic of Darokin) in small vugs.
This formation is composed of Sedaran to Yakhan age volcanic rock, primarily tuffs interbedded with pyroclastic deposits, lahars and the occasional dacitic to andesitic flow. Small pockets of the Altan Tepes batholith are located throughout this formation. These rocks are formed by active volcanism caused the by the Altan Tepes batholith. Ash fall deposits are often capped with paleosols (old soil horizons). Pyroclastic flow deposits (caused from collapsing eruptive clouds) contain woody debris with the consistency of charcoal. Lahar deposits (caused by small amounts of water mixed with material flowing downhill) contain woody debris. The sparse dacite and andesite flows are located in the northeastern part of the formation.
The Parendan period witnessed the beginning of uplift of the Colossus Mountains and the volcanic activity of the Adri Varma traps. Periodic basaltic flows erupted over five million years, oozing lava across the known world. Current magma at depth in the Adri Varma plateau suggests that the eruptive cycle of the basaltic flows is not over. These basaltic flows create the upper portion of the Wendarian Range and sections of the Dwarfgate Mountains. The Black Peak Mountains are capped by these basaltic flows, giving them their name. Paleosols (old soil horizons) are interbedded the basaltic flows and many contain vertebrate fossils. Eruptive centres originated from Adri Varma in the Great Northern Wilderness. Lava flowed to the southeast covering the Black Peak Mountains of the Kingdom of Karameikos. Shallow seas intruded by the basalt created thin layers of salt beds interlayered with dolomite. Low-grade opal, formed by dolomite alteration from the heat of the basalt is located on the contact boundary between basaltic flows. Salt beds near Rymskigrad (Principalities of Glantri) are mined between basaltic flows.
The Black Peak Mountains of the Kingdom of Karameikos are thick beds of basalt with pockets of pillow basalt that contains petrified wood. Agates of good quality are also associated with these flows and are eroded into the nearby streams.
This formation is composed of early to late Parendan age continental sedimentary rocks, including tan to dark grey fluvial sandstones and grey to black siltstones. Ash beds in coal of early Parendan age are located near Highhold (Kingdom of Ostland) contain sparse fossil leaves, amber and petrified wood. Tan sandstone interfingered with red conglomerates of mid to late Parendan age are located near Hostpork (Soderfjord Jarldoms) contains sparse fossil vertebrates. Amber often washes onto beaches after strong storms, implying large amber deposits are within the sea. Often amber is found within the root systems of kelp stalks.
Coal near Highhold (Soderfjord Jarldoms) is of good quality (bituminous) and is mined and exported to Rockhome for smelting operations. Amber and petrified wood is mined nearby for ornamental use.
This formation is composed of middle Sarkesan to early Parendan age white to grey limestone, interbedded with grey siltstone and black to grey shale. Middle Sarkesan age white limestone deposits within the eastern Khanates of Ethengar have formed into karst topography, creating massive sinkholes. These limestones also contain a diverse assemblage of macro-marine fauna. Late Sarkesan to early Parendan thickly bedded grey limestone becomes increasingly interbedded with grey siltstone and black shale to the southeast. Marine fossil diversity diminishes as it enters into the early Parendan. Interbedded siltstones and shales contain fossil plants, with a high diversity of ferns and horsetails. Along the contact with the Altan Tepes intrusive rock, contact metamorphism is present, creating wide skarn zones. Most of these deposits contain high amounts of metallic minerals (see Yakhan age).
Sarkesan - Sadeffan
This formation is composed of Sadeffan to Sarkesan age oceanic plate, imbricated onto the continent of Brun. Most scholars refer to this as the Tel Akbir Ophiolite suite. The lower parts of the sequence are composed of dunite with minor amounts of peridotite, mostly altered to serpentinite. Podiform chromitite, silica carbonate, mercury, nickel, gold and magnesite are common throughout this layer. As the dunite grades into pyroxenites and gabbros, asbestos, nickel and cobalt is commonly found. Gabbros then grade into sheeted basaltic dykes and into basaltic flows. The top layer is composed of marine sedimentary rock, with areas of brecciation, especially in areas that hydrothermal expulsion occurred (such as black smokers).
Podiform chromite deposits in dunites are extensive throughout the Island of Mositius and Borydos Island. The Thyatian Navy occasionally collects these rocks for ballast in the bilge of large ships. Marine sedimentary rocks, mostly metamorphosed into black argillite and grey to blue phyllite exist throughout the Island of Hattias and brecciated sulphide pipes have been found throughout the island. Marine meta-sedimentary rocks also occur within the area of Fort Zendrol.
Large nickel deposits associated with mercury and gold occur in dunites near Surra-Man-Raa (Emirates of Ylaruam).
Dunite grading into pyroxenites on the eastern edge of the Kingdom of Ostland contain significant amounts of magnesite, nickel, and asbestos. Small dwarven mining operations mine magnesite and asbestos at this location.
Dunites with peridotite are located in the east of the Heldannic Territories. They are associated with small pockets of chromite and magnetite. The magnetite is mined for iron production, but the chromite is used as ballast in ships constructed in Freiburg.
This formation is composed of Sarkesan-Sadeffan age thick-bedded grey marine shale, bright red siltstone and red to grey sandstone (deltas) grading into low-grade metamorphic red to grey slate to the northwest. Middle Sarkesan age thick-bedded grey shale located near Tromso (Vestland) contains a diverse assemblage of macrofauna, with a high diversity of ammonites. Some of these ammonites have mother of pearl layers exposed and are mined for gemstone use. Late Sarkesan age deltaic sandstones located near Dovefell (Vestland) are interspersed with lahar deposits that contain small fragments of petrified wood and sparse fossil leaves. Late Sadeffan age oil shale is interbedded in marine shales south of Freiburg (Heldannic Territories). Tar associated with this oil shale is mined for ship construction in Freiburg. Low-grade metamorphism from late to middle Sadeffan shale to slate begins approximately 75 miles southeast of Grauenberg (Heldannic Territories). Large slate sheets are mined near Grauenberg for building material (roofs) and export.
This formation is composed of late Sadeffan age metavolcanic rocks composed of highly altered tan to orange meta-basalt and pyretic rich hydrothermal deposits ('black smokers'), associated with the Tel Akbir Ophiolite Suite. This formation is the upper portion of the Tel Akbir Ophiolite suite, imbricated into the Continent of Brun. The meta-basalt is highly altered, often capped with a clay-weathered surface. Hydrothermal deposits, formed by high temperature water and gases from intrusive mafic rocks have created rich ore deposits, primarily sulphide in origin. High values of gold and silver have been reported in the Barony of Buhrohur and the Barony of Biazzan (Empire of Thyatis). Contact margins with the Altan Tepes have produced large mercury deposits, which are actively mined by the dwarves in the Barony of Buhrohur, particularly for export to Rockhome.
This formation is composed of early to middle Sarkesan age grey shale interbedded with black oil shale grading into black to green slate. Small artesian pools of tar are reported near the cliff of the Atruaghin plateaus. Small bands of grey to red chert and flint are interbedded with slate and are mined on the hills near the Atruaghin plateaus.
This formation is composed of Sadeffan age quartzite, interbedded with bands of schist. This quartzite is predominantly fine grained and thinly bedded. However, thick bedding near Feador (Kingdom of Alfheim) contains quartzite of remarkable clarity. Miners in small mines carefully remove pieces of this quartzite for jewellery and for reprocessing into glassware. A small layer of schist, located north of Fort Hobart (Republic of Darokin) contains staurolite crystals of good quality.
Schist layers east of The Cairn (Republic of Darokin) have shown minor amounts of haematite.
Moghsan - Hushran
This formation is composed of Moghsan age mixed metamorphic and igneous rock. Igneous rocks consist of primarily tonalite, occasionally grading into diorite. Rarely, dacite and andesites occur within the formation. Metamorphic rocks include high-grade schist and gneiss. Large reserves of ore deposits, primarily sulphides occur within this formation. A large mercury deposit associated with andesite is reported near the Naga River, near the confluence of the two rivers.
This formation is composed of early to mid-Moghsan age phyllite interbedded with argillite and quartzite. This formation is poorly exposed with only the occasional outcrop. Placer deposits located on the Streel River contains silver and minor amounts of gold, suggesting ore deposits exist within the Khanates of Ethengar.
This formation is composed of early to mid-Moghsan age amphibolite grading into greenstone to the west. The amphibolite has large euhedral (well crystallised) plagioclase feldspar crystals and porphyroblasts of grossular garnet and twinned staurolite. Long kyanite crystals in Crossbones (Thyatis) are reported within the near shore sand deposits. Metallic mineralisation is rare, but native silver is reported on Fortress Island (Minrothad Guilds) and is actively mined.
This formation is composed of mid to late Moghsan age metaconglomerate and metasandstone, primarily of greenschist and greenstone lithology. Almandine and grossular garnets are found within the gravel of the metaconglomerates and metasandstones. Silver and haematite are also located within the gravel, especially where the metaconglomerates and metasandstones near bedrock. A paleo-river bed (metasandstone) located near Highforge (Kingdom of Karameikos) has yielded high quality silver and iron. Almandine garnets of good quality have also been found near this location. Iron (in the form of magnetite) in paleo-riverbeds is reported near Penhaligon (Kingdom of Karameikos). Agates of various sizes are located near Rifllian (Kingdom of Karameikos) within an eroding outcrop.
This formation is composed of early Hushran age white to tan limestone and white marble. Thick-bedded limestones near Briddleton (Empire of Thyatis) are associated with marine fossils, with a high diversity of crinoids. Marble located near Retebius (Empire of Thyatis) has good qualities for quarry stone and sculpting. Contact zones with the Altan Tepes intrusive rock has created small ore deposits in skarn. Gold nuggets first found in placer deposits on the Polithius River were thought to have come from this contact. There is some truth to this; however, the skarn ore deposits contained high amounts of sulphides, particularly copper sulphides. However, most of the gold found was eroded from the Altan Tepes range from small veins of free mill gold.
This formation is composed of late Hushran to late Moghsan age white to grey limestone, often interbedded with tan to black siltstone and occasional red to brown sandstone. This formation, known as the Hurgon Sequence by the dwarves of Rockhome, forms most of the Hardanger Mountains. Spectacular outcrops located on the Ostfold Scarps produce numerous macro marine fossils of early to late Moghsan age, with high diversity of large fish. A small quarry in Wilmik (Soderfjord Jarldoms) has produced building rock of good quality, often with numerous brachiopod and trilobites visible. Water from the headwaters of the Saltfjord River has formed numerous underground caves and some karst topography.
Contact with the Altan Tepes batholith has created large skarn deposits. These skarn deposits are rich in metallic minerals and sometimes contain large vugs (see YAPAi). The Great Marsh, located with the Soderfjord Jarldoms contains large amounts of bog iron and supplies much of the local iron use. There has been some speculation as to the origin of the iron, as limestone does not carry iron in any great quantity. Most scholars of the day have concluded that glacial deposits located throughout the Hardanger Mountain Range are the source.
This formation is composed of mid-Moghsan to early Hushran age greenstone (low grade metamorphic rock) with minor amounts of hornfels and amphibolite. The greenstone has subhedral (partially formed) pyroxene crystals. Minor ore deposits of quartz veins, associated with tin and silver is located near Dolos (Republic of Darokin). Undiscovered veins near the ruins of Ardelphia (Republic of Darokin) are associated with silver and gold in quartz veins.
Surficial deposits near the Malpheggi Swamps have produced significant quantities of peat, which is harvested outside of Port Tenobar and Athenos (Republic of Darokin). Low-grade coal (lignite) has been found near Fort Nar. Small-scale miners have mined these deposits, but buyers are scarce due to the low quality of the coal.
This formation is composed of Hushran age hornfels with minor amounts of marbles and schists, subjected to hydrothermal alteration. This formation, known as the Kurkrest Sequence by the dwarves of Rockhome, forms most of the Cruth Mountain Range. Hornfels contain euhedral (well crystallised) hornblende crystals, with anhedral (poorly formed crystals) pyroxene and mica. Quartz veins within the hornfel (predominantly) contain concentrations of copper (predominantly covelite), iron (minor haematite), lead (galena, with concentrations of gold and silver), and zinc (sphalerite). Small veins of mercury (cinnabar) are also located here. Meta-volcanic altered rock found in the northwest of the Cruth Mountains contains tin associated with silver. The town of Longflask (Five Shires) is located on a place where a metavolcanic deposit is near rich quartz veins.
Tourmalines of a variety of colours and almandine garnets have been found in large quantity near Ober's Mumbur (Five Shires). Both the tourmaline and garnets are of good quality, some containing remarkable clarity. Other gemstones could be found with more exploration.
This formation is composed of middle Kavashan age limestone interbedded with shale and siltstone. This limestone probably extends into the Great Waste, but is capped by the Adri Varma basalt. Some macro marine fossils have been found on the cliffs of the Great Waste.
This formation is composed of argillite interbedded with phyllite. The Kurish Massif is composed of this formation. The dwarves of Rockhome refer to this formation as the Kurreft Sequence. This formation contains black to brown crumbly argillite, grading into grey siltstone and interbedded with phyllite and green schist. Quartz veins brecciate argillite in small pockets, especially near the Peshmir volcano. These brecciated areas sometimes contain valuable minerals. Silver mines near Latehar are mined in a large mass of breccias. Fluorite of purple and green colour, associated with yellow barite and quartz is located near Raneshwar (Sind). Small mines have produced large barite crystals and some fluorite crystals.
Cavern systems within this formation are not geologic in formation. Huge burrowing creatures have burrowed through this ground, creating extensive caves. It is unknown if these caves still contain the creatures that have created these caves.
Argillite within this formation easily erodes. During the monsoon season, heavy rains trigger numerous landslides, often in debris flows and earth flows. Much of this material flows into Lake Hast and helps to settle the fowl black material flowing into Lake Hast from the Adri Varma plateau.
Mahian - Morjan
This formation is composed of early to middle Mahian age moderately bedded green to black shale, interbedded with thinly bedded grey siltstone and thickly bedded white to grey limestone. The Mengul Mountains are partly composed of this formation. Middle Mahian age shale grades into slate near the City of Wendar (Kingdom of Wendar) and into higher grades of metamorphism near the Mengul Mountains. Ore deposits have formed near the contact of the intrusive rock in the Mengul Mountains, especially where limestone is located. Shale near Oakwall (Kingdom of Wendar) contains macro-marine fauna, with a high diversity of fish.
This formation is composed of middle Morjan to early Mahian age metasedimentary beds, primarily thickly bedded grey to blue phyllite, interbedded with thickly bedded black argillite and thinly bedded green to blue schist. Highly deformed, paleo-bedding is difficult to determine. Kyanite in gem quality is located near the contact with the intrusive rock of the Mengul Mountains. Almandine garnets are reported near the contact areas in schists. Sulphides and other ore bearing minerals have been northeast of Bengarian Hermitage (Kingdom of Wendar). Fractured topaz has been found north of Altendorf (Heldannic Territories). Further exploration could yield unfractured gemstones within this area.
This formation is composed of red to purple phyllite interbedded with green schist and grey to black argillite. The Silver Sierras and the Amsorak Mountains are primarily composed of this formation. The dwarves of Rockhome refer to this formation as the Syrheft Sequence. Thin quartz veins are often associated with galena, rich in silver and gold, and brecciate thickly bedded fine-grained phyllite. Coarse-grained green schist contains a variety of garnets of good quality and tourmaline of moderate quality. Gem quality kyanite located near Corran Keep (Principalities of Glantri) has just begun to be mined (pre-meteorite strike).
Intrusive volcanogenic zones within the deposit are associated with metals of tin, silver, bismuth, antimony and mercury. Other heavy metals are also associated with these, but are more rare.
This formation is composed of Mahian age red, purple and white continental sandstones interbedded with grey to tan conglomerates and occasional volcanic layers, such as tuffs, pyroclastic flows and lahars. Small deposits of sandstone are of good glass making material, being relatively free of impurities, are located near Mahasabad (Sind). It is mined in small quantity for glassware. Lahar deposits near Ft. Anselbury (Republic of Darokin) have produced petrified wood and occasional agate. Amber and coal deposits (of bituminous quality) have recently been located far south of Mahasabad near the Atruaghin Plateau cliffs.
This formation is composed of Mahian marble. The dwarves of Rockhome refer to this formation as the Dulkur Sequence. Coarse grained marble of various colours, predominantly white, with minor red, yellow and green. Fossils of coral, brachiopods and other marine fossils are common within sections of the marble. Marble is actively quarried near Lizzieni (Principalities of Glantri) for use of building material and carving. Placer deposits on the Arnus River are associated with gold and silver with almandine garnets and topazes.
This formation is composed of Mahian age schists with pockets of gneisses and pegmatites. The dwarves of Rockhome refer to this formation as part of the Kuldwyr Sequence Biotite rich blue schist contain high concentrations of metallic mineral deposits on disseminated quartz veins. Garnets are common within the schist. As the schist grades into pink to grey coarse grain gneissic rock, beryl becomes common within the rock with reports of gem quality emerald, aquamarine and chrysoberyl. Pockets of pegmatites are associated with platinum, gold with minor amounts of jacinth. These rocks are highly resistant to erosion, forming high mountains with sheer cliffs.
This formation is composed of Morjan age phyllite, interbedded with grey to blue conglomerate, flaggy argillite and brown meta-sandstone. The Glantrian Alps and Colossus Mountains are mainly composed of this formation. The dwarves of Rockhome refer to this formation as part of the Kuldwyr Sequence. Thin bedding of white quartzite is near the stratigraphic top of this formation. Grey meta-shale (slaty shale) caps this unit and is located on the highest peaks within the mountain range. It contains fossilised coral and other similar marine fossils.
This formation is composed of Kazjdan age coarse-grained gneiss and mylonites. Many dykes of coarse-grained grey to white mylonites intrude pink to grey coarse-grained gneiss. Thick quartz veins brecciate many sections, associated with metallic minerals with high amounts of platinum and trace amounts of mithril. Euhedral to subhedral jacinth, beryl, topaz and garnets is found throughout the gneiss and mylonites.
This formation is composed of Kazjdan age white sandstone interbedded with green to red siltstone and white limestone. Thick-bedded glacial material, capped with limestone is at the base of this formation. After the capped glacial material, an explosion of diversity is contained within the limestone layers (see Cambrian Fossils). A high diversity in Trilobites, Priapulida, Sponges and inarticulate Brachiopods exist within the limestone within this formation.
The town of Moulins (Principalities of Glantri) is a small mining town, with one active platinum mine, associated with gold and aquamarine and two small gem mines, one of emerald and jacinth, the other topaz and garnets.
This formation is composed of early to late Darekhtan age continental sandstone with marine shales, interbedded with limestone. Thick-bedded high-grade coal (bituminous) deposits are located near Eriadna (Principalities of Glantri) but are currently not mined. Hundreds of years ago, the dwarves of Rockhome actively mined these deposits for smelter operations, both locally and in the Kingdom of Rockhome. Originally, the dwarves called this formation the Blyssen Sequence. Small tar pits also occur within this area and are actively mined and exported to most of the areas in the Known World. Gold in paleo-placer deposits and current placer deposits have been located near New Alvar (Principalities of Glantri) and have produced good quantities of gold. Tin and minor amounts of silver have also been found, as well as the occasional diamond. The origin of these continental sediments is not known. Red sandstone near Redstone has been quarried for use of building material within the Principalities of Glantri.
Limestone becomes increasingly interbedded with shales in the Broken Lands, creating karst topography and large caverns. Lahar deposits in the northeast of the Broken Lands have well-preserved petrified wood. Although the majority of the petrified wood has been replaced with quartz, other pieces recovered have been replaced by opal (microcrystalline quartz). Salt deposits from the flooding and drying of 'The Mucks' in northeastern Broken Lands is fed from eroding salt beds in the Principalities of Glantri by the Dol-Anur River. Active geysers and tar pits located in the Black Hills of the Broken Lands are caused by hydrothermal activity at depth. Brave miners on the border between the Republic of Darokin and the Broken Lands actively collect the tar.
Sandstone and shale located on the Atruaghin Clans plateau are predominantly red, with minor amounts of haematite within the layers.
This formation is composed of Gharman age high-grade schist, with pockets of pegmatites. The schist is highly dissected with reverse faulting and deformed with folding. High-grade schist and pegmatites contain concentrations of ore minerals. Pegmatites contain gold crystals and platinum in quartz stringers. Many high quality gemstones have been recovered, such as beryl (emeralds) and corundum (rubies and sapphires) within this formation. Long-term mining is difficult, due to the high-deformed nature of this deposit.
This formation is composed of Gharman age garnet bearing biotite schist grading into coarse-grained gneiss. This formation has a great deal of weathering near the surface and good outcrops are rare. Gemstones eroding out of the rock are found in relict river systems and consist of sapphires, rubies, moonstones, topazes, and garnets. Ore deposits within this formation also exist. Native gold in thin veins erode into streambeds and are actively mined. Native platinum associated with quartz is also found within the paleo-riverbeds and are mined.
This formation is composed of Nozendegan age continental sedimentary rocks, primarily red to grey arkosic conglomerates and sandstones. These rocks are highly weathered near the surface. Outcrops near the cliffs of Ylaruam have shown crossbedding and graded bedding. Some outcrops of conglomerates have concentrations of metallic cobbles, showing high values of gold, copper, and silver. Near the central desert area of Ylaruam, bedded white dolomites and tan sandstones are associated with salt domes and small artesian wells of oil and oil related minerals.
This formation is composed of Akejzan age banded iron formation. Banded iron formations across Mystara formed when oxygen was in high enough quantity to oxidise the oceans. Anoxic oceans absorb high amounts of iron, but precipitate it once it absorbs oxygen. Banded iron formations are often interbedded with chert or siltstone. This formation is actively mined by the people of Ylaruam for iron.