fossil

Triceratops Fossil

Triceratops horridus

Hardness: typically 4-5 on the Mohs scale (rock-like replacement); Color: dark brown, tan, or black depending on mineral content; Luster: dull to sub-glassy; Composition: permineralized bone often replaced by hydroxyapatite, silica, or calcium carbonate.

Hardness: typically 4-5 on the Mohs scale (rock-like replacement)
Color: dark brown, tan, or black depending on mineral content
Luster: dull to sub-glassy

Identified July 19, 2026More fossil →

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Physical properties

Formation & geological history

Formed through permineralization within sedimentary layers, primarily in the Hell Creek and Laramie Formations. These specimens date back to the Late Cretaceous period, approximately 68-66 million years ago.

Uses & applications

Scientific research, museum display, and educational exhibits. Occasionally found in high-end private collections.

Geological facts

Triceratops is one of the most recognizable dinosaurs, featuring three horns and a large bony frill. The name means 'three-horned face.' They were herbivores that lived alongside Tyrannosaurus Rex.

Field identification & locations

Identify in the field by looking for distinct porous bone textures and heavy mineral replacement in Mesozoic sedimentary rocks. Commonly found in the Western Interior of North America (Wyoming, Montana, South Dakota).