Topaz with Hyalite Opal

San Felipe is a Mexican locality for topaz, with crystals found in cavities within the volcanic rocks of the area. The region has produced some very sharp and well-formed topaz crystals.

The hyalite opal is a nice extra feature on this specimen. Hyalite is a clear to translucent form of opal that can coat or grow around the topaz, showing a strong green glow under UV light.