Jasper

Hardness: 6.5-7 (Mohs scale), Color: Red, brown, and yellow hues (due to iron oxides), Luster: Vitreous to dull, Crystal structure: Microcrystalline (trigonal), Cleavage: None (conchoidal fracture), Specific gravity: 2.58-2.91

Formed through the accumulation of fine-grained silica in sedimentary environments or hydrothermal veins. Impurities such as hematite give it the characteristic red color. It can range from various geological periods, often associated with old lake beds or volcanic ash.

Used primarily in lapidary arts for jewelry, decorative carvings, and ornaments. Historically used for making tools due to its conchoidal fracture which creates sharp edges.

Jasper has been used as a gemstone since antiquity. In many cultures, red jasper was believed to be a stone of physical strength and energy. It is an opaque variety of chalcedony.

Identify in the field by its opacity (even on thin edges), its hardness (can scratch glass), and its distinctive waxy/vitreous luster. Common in areas with high silica content or riverbeds where water has polished the stone.