SPHENE
A brilliantly transparent gem, sphene has fire greater than that of diamond! This gem is named from the Greek word for "wedge," as its crystals are typically wedge shaped, but may be referred to by its mineral name, titanite. On rare instances, sphene may be pink, brown or black in color, but is mainly found in a range of green to yellowish green colors. Another characteristic sphene possesses is birefringence, or double refraction, meaning that light splits into two rays as it passes through the gem. As a result, the back facets appear as double images, giving the gem a soft, hazy appearance, similar to the doubling seen in zircon.