Frequently asked questions

• Is spinel actually related to ruby or sapphire?

  Spinel is its own mineral species — magnesium aluminum oxide in the cubic crystal system — and is mineralogically distinct from ruby and sapphire, which are both corundum (aluminum oxide). The confusion is historical: many famous "rubies" in royal collections, including the Black Prince's Ruby in the British Imperial State Crown, were reclassified as red spinel once gemology matured. In bead form the two can look similar at a glance, but spinel tends to read slightly softer in saturation and shows different inclusion patterns under loupe. Spinel is also un-treated in most rough that reaches the bead market, where corundum is routinely heated.
• How is spinel typically treated in the bead trade?

  Spinel is one of the few colored stones still commonly sold untreated at the bead level — most rough does not respond to standard heat treatment the way corundum does, so cutters generally work the natural color. Black spinel, red spinel, and the gray-to-blue ranges Dakota stocks are usually natural. That said, treatment status should appear on the individual listing — ask before buying if it isn't specified. Synthetic flame-fusion spinel exists in the trade as a calibrated, inexpensive bead material in vivid blues and other colors; natural spinel will show subtle color zoning and inclusions that synthetics lack.
• What jewelry projects does spinel work best in?

  At Mohs 8 with a cubic crystal structure and no cleavage, spinel is one of the more wear-tolerant colored stones in the bead range — durable enough for bracelets, rings, and daily-wear pieces that would chip softer materials. The small-size microfaceted rounds (2mm and 3mm) Dakota stocks are useful for delicate spacer runs, multi-strand layering, and accent work next to larger feature stones. Black spinel reads as a sharp, mirror-finished neutral that pairs cleanly with sterling, gold-fill, and oxidized findings. Red and pink spinel sit well next to garnet, ruby, rhodolite, and rose gold.
• How do I tell black spinel from black onyx in a finished piece?

  Black spinel and black onyx are the two main black bead options in the trade, and they look different once strung. Spinel is a harder material (Mohs 8 vs onyx around 6.5–7) and takes a sharper, more reflective polish — faceted black spinel reads almost mirror-like, with crisp facet edges that hold up. Black onyx is typically dyed chalcedony; it polishes to a softer, slightly waxier black and the facets read less sharp. For projects where you want black to act like a gemstone rather than a flat background, spinel carries the light better. Onyx is the budget-friendlier option for larger smooth rounds.
• How should I care for spinel jewelry?

  Spinel is low-maintenance for a colored stone. Mohs 8 hardness and no cleavage plane mean it tolerates ultrasonic and steam cleaning, though warm water with mild soap and a soft brush handles routine cleaning fine. The main concern in finished pieces is the stringing material and any softer beads on the same strand, not the spinel itself. Avoid prolonged exposure to harsh chemicals — chlorine, bleach, and strong solvents can dull the polish over time even on durable stones. Store separately from softer materials like turquoise, opal, or pearl, since spinel can scratch them through normal jewelry-box contact.