For Obsidian we have terms and definitions in 9 topics. The topics are Anthromorphemics, Anthropology, Archaeology, Earth Science, Geologic, Glass, Physical Geography, Rock Art and Volcano.

Obsidian (Anthromorphemics)

A volcanic glass whose ease of working and characteristically bard flintlike edges allowed it to be used for the making of tools.

Obsidian (Anthropology)

A volcanic glass whose ease of working and characteristically bard flintlike edges allowed it to be used for the making of tools.

Obsidian (Archaeology)

Very hard volcanic glass used for tools. It can be dated by measurement of thickness of its hydration layer on surface

Obsidian (Earth Science)

A black or dark-colored volcanic glass, usually of rhyolitic (felsic) composition.

Obsidian (Geologic)

Dark-colored volcanic glass. Usually has the same chemical composition as the extrusive igneous rock, rhyolite.

Obsidian (Glass)

A volcanic mineral that was the first form of natural glass used by humans. It is usually black, but it can also be very dark red or green; its splinters are often transparent or translucent.

Obsidian (Physical Geography)

Glassy dark colored volcanic rock. Usually composed of rhyolite.

Obsidian (Rock Art)

A form of natural volcanic glass used to make projectile points and other tools

Obsidian (Volcano)

Obsidian is dense volcanic glass, usually rhyolite in composition and typically black in color. Compared with window glass, obsidian is rich in iron and magnesium; tiny (<.005 mm) crystals of iron oxide within the glass cause its dark color. Obsidian is often formed in rhyolite lava flows where the lava cools so fast that crystals do not have time to grow. Glass, unlike crystals, has no regular structure and therefore fractures in smooth conchoidal (curved) shapes. The intersections of these fractures can form edges sharper than the finest steel blades. For this reason, obsidian was used by many native cultures to make arrowheads and blades. (USGS/VHP)

Similar

Browse words that start with:

• Ob
• Obs
• Obsi
• Obsid
• Obsidian

Browse All Terms by First Letter

Term Search