Mineral variety Healing crystal

Virgin Valley Opal

Variety of Opal.

📜 Key facts

Age	Miocene (about 16 million years old)
Origin & sources	Virgin Valley, Humboldt County, Nevada, USA. Black fire opal is Nevada's official precious gemstone.
Composition	Precious opal, often replacing wood. It is notoriously prone to cracking (crazing) as it dries. Opal is hydrated amorphous silica (SiO₂·nH₂O), Mohs 5.5–6.5.

How it forms

Silica-rich water seeped into cracks, cavities and fossils, then slowly evaporated. Tiny silica spheres settled out. In precious opal they are stacked in a neat, regular grid that diffracts light into play-of-colour. In common opal they are jumbled.

Mineral data: see Opal.

🌍 Where it's found

Type locality
Notable source / deposit
Country of origin

Marker positions are approximate (region or locality level). Type localities from Wikidata; notable sources curated by Crystopedia.

✨ Metaphysical & Folklore

These are traditional and folk beliefs from crystal lore. They are not scientific or medical claims – crystals are not a substitute for professional care.

Nevada's state precious gem is linked in lore to inspiration and transformation.