Chert (Jasper-bearing)

Hardness: 7 (Mohs scale), Color: Variegated black, brown, and reddish-orange, Luster: Waxy to dull, Crystal Structure: Cryptocrystalline, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formed from the accumulation of silica-rich organic remains such as radiolaria or diatoms in deep marine environments. The iron content produces the reddish jasper-like hues. These rocks are often related to ancient seafloor deposits and can range from hundreds of millions of years in age.

Historical use for sharp tools and weapons (flint-knapping); modern use includes landscaping, jewelry (when polished), and as a collection specimen.

Chert is so hard it can strike sparks from steel. Because of its dense, cryptocrystalline structure, it breaks with a circular 'conchoidal' fracture, similar to glass. This specimen shows significant weathering and staining from iron and manganese.

Identify in the field by its hardness (it will scratch glass), waxy feel, and smooth curved fractures. Found globally, especially in coastal areas like the Pacific Northwest or in limestone beds.