Capelinha Sphene are fiery, lime-green gemstones from a famous mining region near the Brazilian town of Capelinha. A rare exotic gemstone, Capelinha Sphene has a fire greater than Diamonds, high brilliance, and an amazing Diamond-like luster, giving it an intense natural beauty.
Hardness 5 -5.5
Refractive Index 1.843 - 2.110
Relative Density 3.52 - 3.54
Sphene is a relatively new, rare exotic gemstone that remains virtually unknown to most jeweler connoisseurs. Named for its famed locale, the bright lime-greens of Capelinha Sphene are not only one of Sphene’s rarest hues, but are also body colors highly conducive to visible fire (see below).
Sphene’s major value determinants are a dispersion (fire) greater than Diamonds, a strong pleochroism (different colors visible from different angles) that makes it appear to change color, an amazing adamantine (Diamond-like) luster, double refractivity that lends optical depth, an unusually high refractive index affording excellent brilliance, and cutting quality.
Possessing an intense natural beauty, Sphene facets into brilliant, fiery gems, but is notoriously difficult to polish and cutters must use a fine lap. Every Capelinha Sphene has been optimally cut with an eye-clean clarity, the highest quality clarity grade for colored gemstones, to maximize each gem’s fiery brilliance, and a deft polish condition, to maximize luster.
Named from the Greek ‘sfena’ (wedge), because of its wedge shaped crystals, Sphene is also sometimes called Titanite, for its titanium content. Trace elements of aluminum and iron are common with chromium causing the concentrated green color of Sphene. Most Sphene is brown to green to yellowish green, but its intense fiery brilliance can display every spectral color (blue, green, orange, red, violet, and yellow). Fire, also known as dispersion, is the splitting of light into its component colors. This gemological feature adds both beauty and value. While all gemstones of a large size exhibit fire, the most dispersive gemstones ranked in order are: Sphalerite1, Sphene2, Demantoid3, Diamond4, and Zircon5. Inclusions in some Sphene can create the cat’s eye effect (chatoyancy, single bright reflective line of light similar to a cat’s eye). Derived from the French ‘oeil de chat’ (cat’s eye), Chatoyancy is created by the reflection of light from long needle-shaped inclusions occurring in a parallel arrangement. The chatoyancy of Sphene is dependent on it being cut ‘en cabochon’ (cut in convex form and highly polished, but not faceted) with the fibers parallel to the base and is most visible in a direct, single beam of light. Sphene is also renowned for their pleochroism, or more specifically, strong trichroism (three colors) when transparent, displaying three different colors depending on the body color of the stone.
While Sphene comes from Brazil, India, Mexico, Pakistan and Sri Lanka, Madagascar is currently the main source.
Capelinha Sphene is from deposits near the town of Capelinha in the Jequitinhonha Valley in the Brazilian state of Minas Gerais (‘general mines’ in Portuguese). Capelinha is a famous mining region and has produced some of the best (lime-green) Sphene in the world. Unfortunately, the deposit is ostensibly depleted, not producing anything commercial for close to 20 years, making Capelinha Sphene virtually unattainable in the marketplace.
Usually smaller than 1 carat, larger eye-clean Sphene is geologically scarce. Capelinha Sphene is also a totally natural gemstone and not enhanced or treated in anyway.
Durability & Care
An exotic jewelry gemstone (Mohs’ Hardness: 5 – 5.5), Capelinha Sphene should always be stored carefully to avoid scuffs and scratches. Clean with gentle soap and lukewarm water, scrubbing behind the gem with a very soft toothbrush as necessary. After cleaning, pat dry with a soft towel or chamois cloth.