Large Rainforest Jasper Thick Display Slab from Western Australia (Polished One Side)

Description

Rainforest Jasper is the trade name for this very colorful type of Rhyolite that was formed during an eruption of the long extinct Mount Hay Volcano near Queensland, Australia about 120 million years ago. Rain forest jasper gets its name because the mixture of green, red, yellow, brown, and orange colors reminds people of a rainforest canopy.

It is a volcanic rock with high silica content that is formed by eruptions of granitic magmas. Granitic magmas are very dense and cool slowly allowing a lot of time for large crystalline structures called phenocrysts to form in the spherical cavities (orbs) created by gas bubbles in the flow. These cavities are often lined with opal and tridymite. The phenocrysts are typically silica based minerals such as quartz and chalcedony of different colors and are what give rainforest jasper its unique appearance. The stone is also known as rainforest rhyolite, orbicular jasper and spherulitic rhyolite.

Weighs 22 oz or 1.38 lbs (627g) and measures 11.7 x 4.6 x 0.48 inches (29.7cm x 11.7cm x 12.4mm)