Rocks

Pyroxenite is an ultramafic igneous rock that contain pyroxene group minerals such as augite, diopside, hypersthene, bronzite or enstatite. This is a coarse-grained rock...

Ignimbrite is an expansion of hardened tuff. Ignimbrites are igneous rocks made up by crystal and rock fragments in a glass-shard groundmass, albeit the original texture of the groundmass is probably obliterated due to high degrees of welding. The term ignimbrite isn't always encouraged by means of the IUGS Subcommission on the Systematics of Igneous Rocks.

Boji Stones, also known as Moqui Marbles or Shaman Stones, are small, round, naturally occurring stones found in the Navajo Sandstone formation of Utah...

Agglomerate rock is a type of sedimentary rock that forms through the accumulation and cementation of coarse fragments of various sizes, typically ranging from...

Diabase, also known as dolerite, is a type of igneous rock that holds significance in the field of geology due to its unique characteristics...

Lamprophyre is ultrapotassic igneous rock that is occurring as dikes, lopoliths, loccoliths, stocks and small intrussion. It is alkaline silica-undersaturated mafic or ultramafic rocks...

Oil Shale is organic-rich sedimentary rocks that have contain kerogen (insoluble organic matter in sedimentary rock. When subjected to intense heat, these shales yield...

Diatomite, also known as diatomaceous earth, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white...

Flint is a naturally occurring sedimentary rock composed primarily of microcrystalline quartz, or silicon dioxide (SiO2). It is renowned for its historical significance and...

Moon rocks are rocks or regolith (the loose, fragmented material on the surface of the Moon) that have been collected during various Apollo missions...

Claystone is a sedimentary rock composed primarily of clay-sized particles, which are minerals that are less than 0.004 millimeters in diameter. It belongs to...

Greenschist is a metamorphic rock that forms under low-grade metamorphic conditions. It is named for its green color, which is primarily due to the...