Howlite (Dyed Turquoise)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Rock Type: mineral

Physical Properties
Hardness: 3.5 on Mohs scale; Color: Naturally white, but here dyed blue; Luster: Sub-vitreous to earthy; Crystal structure: Monoclinic; Cleavage: None visible in massive form; Specific Gravity: 2.45-2.58
Formation & Geological History
Formed in evaporite deposits as nodules. This specific specimen has been chemically dyed to mimic turquoise. Natural howlite is commonly found in desert environments where borate minerals accumulate.
Uses & Applications
Used primarily in decorative jewelry, beads, and stone carvings. Because it is porous, it is the most common material used to create turquoise imitations.
Geological Facts
Natural howlite is actually white with grey or black veins. It was first discovered in 1868 near Windsor, Nova Scotia, by Henry How. It is often sold under trade names like 'Turquernite' when dyed blue.
Field Identification & Locations
Identify in the field by its softness (it can be scratched by a steel needle, unlike real turquoise which is harder) and the appearance of white color if the stone is chipped or scratched, revealing the dye does not penetrate the center.
Identified on: 4/28/2026
Mode: Standard