sedimentary

Dinosaur Bone (Gembone)

Silicified Dinosaur Bone (SiO2 replacing organic tissue)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Multi-colored patterns of red, brown, blue, and black cells; Luster: Vitreous to waxy; Crystal structure: Cryptocrystalline (Microcrystalline Quartz); Specific Gravity: 2.6-2.7

Hardness: 6
Color: Multi-colored patterns of red, brown, blue, and black cells
Luster: Vitreous to waxy

Identified May 23, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through permineralization where silica-rich groundwater fills the cellular cavities of dinosaur bone over millions of years (primarily Mesozoic era). The organic material is replaced by Agate, Jasper, or Chalcedony.

Uses & applications

Highly prized by lapidary artists for jewelry, cabochons, and knife handles. Also a significant collector specimen for paleontologists and rockhounds.

Geological facts

Gembone is one of the distinct fossil types where the internal marrow and cell structure are exquisitely preserved in semi-precious stone. Most high-quality specimens date back to the Jurassic period, roughly 150 million years ago.

Field identification & locations

Identify in the field by looking for the distinct 'honeycomb' or 'stippled' cellular pattern on the surface. Commonly found in the Colorado Plateau regions of Utah, Colorado, and Wyoming (Morrison Formation).