... One of the stones I received is marked "Genuine Black Star
Sapphire". It's about 8mm by 10mm and an absolutely gorgeous shade
of deep black. There is a small problem with the star. Instead of
showing the normal six pointed star I am used to seeing on sapphires
the stone's star has only four points. It is clearly visible and the
rays form a cross.
Amy, from your description, I’d guess that what you have is probably
star siopside. Sometimes also (incorrectly) called star enstatite,
the stuff is mostly from India. Much softer and more fragile than
sapphire, and much much cheaper too. The “star” doesn’t look quite
the same, so you can visually tell the difference easily. While it’s
possible to have a black star sapphire with only two rays, not three
(two rays give four points), they will still intersect at a 60 degree
angle. With star diopside, while the angle is not quite 90 degrees,
it’s much closer, and will look much more like a cross than a
sapphire with a missing ray. also, with Diopside, you’ll notice that
the two rays are not the same. One is usually slightly
longer/stronger/wider than the other. The difference in
sharpness/width between the two rays is almost always easy to see.
The degree to which you’ve been cheated (if at all) would depend on
whether you paid for a star sapphire, and got this, or whether you
just paid for whatever and this came incorrectly labeled… either
way, if this is a diopside, it’s not even remotely related to sapphire
as a gem, though it might come from a similar region of the world.
And as noted, the values difference between the two types of gem is
very substantial, in addition to the great differences in hardness and
durability.
Nevertheless, Diopsides (since you’ve got it, after all), are still
pretty stones. I’d recommend, though, that if you have it put in
jewelry, put it in something that will get less wear than a ring. It
would be fine in a pendant. In a ring, unless the design protects it
very well, chances are it won’t last long…
Hope this helps.
Peter Rowe