Howlite

Howlite is a calcium borosilicate hydroxide mineral, chalky white to gray-white with web-like veining in gray, black, or brown. Its soft, porcelain-like surface and high porosity make it one of the most recognizable ornamental stones on the market. Chemically it sits in the borate family with the formula Ca₂B₅SiO₉(OH)₅, and it forms in nodular masses that resemble cauliflower heads before cutting.

Howlite Origin and Key Properties

Howlite was identified in 1868 by Canadian chemist and mineralogist Henry How, who examined specimens pulled from a gypsum quarry in Nova Scotia. Today the largest commercial deposits are in California, particularly at Tick Canyon in Los Angeles County and the Lang borate district. Additional sources include Nova Scotia, Russia, Germany, Turkey, and Mexico. The stone grows as nodular masses inside evaporite deposits alongside borax, ulexite, and colemanite, which explains why most rough arrives in rounded, kidney-shaped lumps rather than crystals.

On the Mohs scale, Howlite rates 3.5, which places it among the softer stones used in jewelry — closer to calcite than quartz. It is opaque with a sub-vitreous to porcelaneous luster and a specific gravity of about 2.53 to 2.59. Base color runs from bright white to off-white or pale gray, with the characteristic dark matrix running in thin veins across the surface. Stones without veining are sometimes sold as White Buffalo Stone, though true White Buffalo Turquoise from Nevada is a separate material.

Treatment disclosure matters with this stone. Howlite's porous structure absorbs dye readily, so a large share of the market is dyed — most often blue or green to imitate turquoise, but also red to mimic coral and black to pass as onyx. Reputable sellers label dyed Howlite clearly. At SilverRush Style, we identify dyed pieces as dyed Howlite and sell natural white Howlite under its own name.

Howlite in Sterling Silver Jewelry

Most Howlite in our inventory is cut as cabochons — ovals, rounds, rectangles, and freeform shapes that showcase the veining. Beads, tumbled nuggets, and carved shapes also appear in strung designs. The stone is rarely faceted because its softness and opacity don't return light the way quartz or beryl do. Sterling silver (.925) suits Howlite well: the cool gray metal picks up the gray matrix lines and frames the white body without competing with it. Our howlite jewelry collection covers rings, pendants, earrings, and bracelets, with most pieces priced between $25 and $90 depending on stone size and setting weight.

Because Howlite is soft and porous, it works best in pieces that don't take daily abrasion — pendants, earrings, and occasional-wear rings outlast everyday bands. If you want a white stone for a stacking ring worn during housework or the gym, consider a harder alternative like white agate or white topaz.

Care and Cleaning

Clean Howlite with a soft cloth dampened in lukewarm water and mild soap, then dry immediately. Skip ultrasonic and steam cleaners — vibration and heat can fracture the stone and lift dye from treated pieces. Keep it away from household chemicals, perfume, hairspray, and prolonged sunlight, which can fade dyed stock. Store each piece in a soft pouch, separate from harder gems that would scratch the surface.

Frequently Asked Questions