Apr 23, 2023 · Chert is a fine-grained sedimentary rock composed of quartz (SiO2) that is microcrystalline or cryptocrystalline quartz. It is usually organic rock but also occur inorganically as a chemical precipitate or a diagenetic replacement. It occurs as nodules, concretionary masses, and as layered deposits.

In prehistoric times, chert was often used as a raw material for the construction of stone tools. Like obsidian, as well as some rhyolites, felsites, quartzites, and other tool stones used in lithic reduction, chert fractures in a Hertzian cone when struck with sufficient force.

Chert is a biochemical sedimentary rock made from microcrystalline quartz. It is very hard – registering a 7 on the Mohs hardness scale, and displays conchoidal fracturing. Chert can almost any color, but is usually gray, brown, red, or green. It has many subvarieties including flint, jasper, agate, and onyx.

Popular varieties of flint, chert, and volcanic glass for flint knapping. Expertly spalled, graded, heated, and cleaned stone for lithic reduction.

Jan 8, 2020 · Chert is widespread, but not widely known by the public as a distinct rock type. Chert has four diagnostic features: the waxy luster, a conchoidal (shell-shaped) fracture of the …

Explore the world of chert, a cryptocrystalline quartz rock valued for its historical significance in tool-making and its modern uses in construction, jewelry, and decorative arts. Learn about its formation, types, and care in this comprehensive guide.

Chert is a sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO 2). It occurs as nodules, concretionary masses, and as layered deposits. Chert breaks with a conchoidal fracture, often producing very sharp edges.

Nov 11, 2019 · RAW CHERT 1" Mineral Specimen Sometimes referred to as flint, Chert is a sedimentary rock rich in silica. This specimen is perfect for teaching geology students about the many forms of quartz, hardness, crystal habit, and fracture. SELECTED & LOCALLY PROCESSED BY A GEOLOGIST

Chert is the proper name for the vast majority of raw materials from which the hafted bifaces ("arrowheads") and other stone tools of east-central Illinois were fabricated. In Europe similar appearing material would be referred to as flint. Both are rich in silicon dioxide (SiO 2).

Chert is a hard, fine-grained sedimentary rock composed almost entirely of silica (SiO₂) in the form of microcrystalline or cryptocrystalline quartz. Known for its durability, waxy or dull luster, and conchoidal fracture (smooth, curved breaks similar to glass), chert is often formed from the accumulation of siliceous skeletons of ...