Dugway Geodes

Dugway Geode Rock Professor Image

DUGWAY GEODES Juab County, Utah
These unusual single and multi-cavity geodes are Utah's version of Thunder Eggs. Within a rhyolite exterior shell, druzy and crystalline quartz-lined cavities were formed by silica-rich fluids seeping into cavities formed in the rhyolite.

Some geodes have up to 5 or 6 crystal pockets, some are connected to each other, and some have small islands of banded rhyolite "floating" between the cavities. The geodes are dug from sediments formed by the ancient Lake Bonneville, and range from tiny up to about 1 foot in diameter.

Geode material: Rhyolite, Quartz ♦ Transparency: Opaque with translucent crystals ♦ Luster: Adamantine ♦ Color: Earth color, crystals are lavender gray ♦ Locality: Juab County, Utah