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Organic Gems: Petrified Wood & Fossilized Dinosaur Bone

Fossilized Dinosaur Bone Jewelry

Petrified Wood & Fossilized Dinosaur Bone

Source: South Dakota, USA, Africa, Europe, Russia

The word 'Fossil' is derived from the Latin word fossus, which literally means "having been dug up." Fossilization is a rare occurrence because most of the organic components that make up plants and animals tend to decompose relatively quickly following death. In order for an organism to become fossilized, the remains need to be buried within sedimentary material as soon as possible.

Petrified Organic Material

Petrification can occur when an organism (plant or animal) comes to rest in an anoxic (oxygen-free) environment such as at the bottom of a lake or on the sea-bed. After petrification, the material takes on the physical properties of a rock-like cryptocrystalline mineral.

At the end of the Cretaceous period around 65 million years ago, dinosaurs suffered a sudden and catastrophic extinction due to a major climatic event brought on by a possible comet or meteor strike. This event ended the dinosaur's dominance on land.

Fossilized Dinosaur Bone Earrings

Fossilized Dinosaur Bone Earrings

   Fossilized Ivory Earrings

Fossilized Ivory Earrings by Jeff & Susan Wise

Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. An animal's bones and skeletal structure are made through a process called "endochondral ossification," which is one of two types of bone formation (ossification), and is the process responsible for much of the bone growth in vertebrate skeletons.

Carbonization & Trace Fossils

Trace fossils are created when only a trace or an impression from the organism provides visible evidence of the plant or animal as with a process called "carbonization." When soft organic material such as leaves slowly decompose, the oxygen, hydrogen, and nitrogen are driven off, and only the carbon molecules remain behind as a thin carbon film.


Dendrites are delicate branching patterns which resemble a wispy fern or moss. Dendrites are produced by certain minerals which crystallize in a pattern that is similar to frost on a window.

Fossilized dinosaur bone, wood or ivory used in jewelry is a very soft material, and can easily be scratched, dented, or fractured. Fossilized and/or petrified plants, ivory tusks, and seashells also make beautiful selections in contemporary jewelry design. Artists like Michael Zobel, Carolyn Morris Bach, and Jeff and Susan Wise use fossilized materials, petrified bone, and dendrites as a textural contrast to semiprecious gemstones. Fossilized bone and wood can have a similar appearance and color to agate and jasper.

Fossilized Dinosaur Bone Properties

Crystal System cryptocrystalline
Mohs Hardness Scale 3.5 to 6.0
Refractive Index 1.54 to 1.55
Specific gravity (SG) 2.5 to 2.9
Surface Luster resinous
Toughness poor
Fracture conchoidal
Gem Color cream, yellow-orange, brown, red, black
Chemical Composition CaCO3

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Bibliography and Reference on Petrified Wood & Fossilized Dinosaur Bone

1. Paul R. Shaffer, Rocks, Gems and Minerals . Martin's Press

2. CFDC, Fossilization & Permineralization . www.discoverfossils.com

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