June in the northern hemisphere is known for sun and blooms and a revelry of rich colors. Maybe not this year with all the rain and dark gloomy days, but even if the flowers are less than normally spectacular we can still look at the gemstones associated with this month. Yes, that is a plural. There are three stones assciated with June; pearl, moonstone, and alexandrite. Three completely different materials sharing one thing in common: they all feature non-static color!

Three Gorgeous Gems
Pearls are not exactly minerals but rather the result of an organic process. These are further divided into salt water and fresh water types. The latter tend to have a much thicker nacre (coating) than the former and can form in multiples per mollusk (generally oysters). Given the same size pearl, a freshwater pearl will consist of mostly nacre while the salt water pearl is mostly irritant with a thin coating of nacre. Both types come in a variety of colors with the famous Tahitian black pearls being among the most expensive pearls in the world.

An example of this birthstone in a piece of jewelry is the necklace, Sweet Serenade

Moonstones come in a variety of pale colors varying most notably from white to grey to peach, but other colors exist. My favorite is rainbow moonstone which shows flashes of color called adularescence. Adularescence is an effect of the crystalization forming plates and reflecting colors in a specific manner. Moonstone is a gem quality type of feldspar and another material also a gem quality feldspar is labradorite which is famous for its “shiller” which is yet another form of reflective play of shifting colors.
My moonstone piece is not yet ready for the web, but I do have an example of Labradorite to show you. The focus of these handmade bead netting earrings are the labradorite faceted briolettes.

Labradorite Earrings using bead netting

Alexandrite is a true dichroic mineral whose color changes depending on the type of ambient light incident on it. Before the advent of artificial light this dicroism was demonstrated by comparing the material in daylight (candescent) and candle light (incandescent) (unless, of course one considers candle light to be artificial). Theoretically, in daylight the gem is green while in candle light it is raspberry red. As it turns out, the gem does not actually change color, but rather depends both on the type of light hitting it and the angle at which it is viewed. There is a variety of candescent/incandescent colors and in general if one is excellent the other is only so-so. Alexandrite is a gem quality chrysoberyl.

I love all three of these materials but by far the rarest is the alexandrite, of which I have only handled one real one. Most alexandrites are man made and I believe this may be the most rarest of gemstones as well as one of the most beautiful.

This entry was posted on Wednesday, June 24th, 2009 at 12:50 PM and is filed under Good to Know. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.