mineral

Dyed howlite (turquoise imitation)

Howlite, Ca₂B₅SiO₉(OH)₅; commonly blue-dyed

AI-generated identification · may be incorrect

White to gray, opaque, blue-dyed surface with dark gray veining; vitreous to porcelain luster and massive, noncrystalline texture. Mohs hardness 3–3.5, brittle, with uneven fracture and specific gravity about 2.5–2.6.

Identified August 28, 2026More mineral →

Explore Dyed howlite (turquoise imitation) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Howlite forms as a borate mineral in evaporite-related hydrothermal deposits, generally in Cenozoic sedimentary settings. The blue color is artificial, produced by soaking porous howlite in dye; the specimen appears tumbled and polished.

Uses & applications

Used for inexpensive beads, cabochons, carvings, and decorative objects marketed as “turquoise.” It has little industrial use beyond ornamental applications.

Geological facts

Natural howlite is usually white with gray or black spiderweb veining; vivid, evenly distributed blue strongly indicates dye treatment. Dye may concentrate in cracks and can transfer with acetone or alcohol.

Field identification & locations

Commonly found in California and Nova Scotia, Canada, with other deposits worldwide. Check drilled holes or chipped areas for white interiors; turquoise is typically harder (Mohs 5–6) and denser.