THE GEMSTONE LIBRARY
Blue Cap Tourmaline
Blue Cap Tourmaline is the collection name for these blue tourmaline crystals associated with quartz. The photographs below show four special specimens from our December 2025 collection.
Tourmaline and color zoning
Tourmaline is a group of related minerals rather than a single composition. Individual crystals can develop different color zones as the chemistry of their growth environment changes. A contrasting tip or cap is one possible expression of that growth history.
Blue and greenish-blue tourmaline is often described as indicolite in the gem trade. Color alone does not identify its precise mineral species or establish copper content. The Blue Cap name is used here as a descriptive collection label, not as a separate mineral species.
These specimens
The collection is presented under its supplied Blue Cap Tourmaline in Quartz identification. No specimen-specific laboratory report or exact mine locality is attached to this page. The four photographs are collection illustrations; no main profile photograph has been assigned.
Collection photographs
Sources
GIA — Tourmaline Description · GIA — Tourmaline color zoning