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Don Crabtree
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Don Crabtree
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Articles about Don Crabtree
Obsidian
Obsidian is a natural volcanic glass formed when silica-rich lava cools too quickly to crystallise, giving it a glassy, dark and sharply fracturing structure. Prehistoric people worked it into blades, projectile points and mirrors by knapping, and because each…
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ObsidianObsidian is a natural volcanic glass formed when silica-rich lava cools too quickly to crystallise, giving it a glassy, dark and sharply fracturing structure. Prehistoric people worked it into blades, projectile points and mirrors by knapping, and because each…