Minerals
A mineral is a naturally occurring chemical compound usually of crystalline form and not produced by life processes. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids. The study of minerals is called mineralogy. To meet the definition of “mineral” used by most geologists, a substance must meet five requirements:
Onyx
Onyx is a type of chalcedony, which is a microcrystalline form of quartz. It is a banded variety of chalcedony that forms in concentric...
Bentonite
Bentonite is a type of clay that is composed primarily of the mineral montmorillonite. It is a highly absorbent clay that has many uses...
Illite
Illite is a type of clay mineral that belongs to the group of non-expanding or non-swelling phyllosilicate minerals. It is a common constituent of...
Smectite
Smectite minerals are a group of phyllosilicate minerals that are characterized by a layered structure and the ability to swell when exposed to water....
Alexandrite
Alexandrite is a rare gemstone that belongs to the chrysoberyl family. It was first discovered in 1830 in the Ural Mountains of Russia and...
Jadeite
Jadeite is a mineral that belongs to the pyroxene group, which is a group of rock-forming silicate minerals. It is one of two types...
Emerald
Emerald are a type of gemstone that belong to the beryl family, which has the chemical formula Be3Al2(SiO3)6. They are valued for their intense...
Ruby
Ruby is a gemstone and a variety of the mineral corundum (Al2O3) that is distinguished by its red color, which is caused by trace...
Sapphire
Sapphire is a precious gemstone that is a variety of the mineral corundum, which is composed of aluminum oxide. It is typically blue in...
Agate
Agate is a fascinating and versatile mineral that has captivated human interest for thousands of years. Agate is a variety of chalcedony, a mineral...
Chalcedony
Chalcedony is a mineral that is composed of microscopic crystals of quartz. It is a cryptocrystalline form of silica, meaning that its crystals are...
Amethyst
Amethyst is a mineral that belongs to the quartz family, known for its purple to violet hue. It is a popular gemstone used in...
