New to Mineral Collecting? Trinity Sells and Educates!

Keith over at Trinity Mineral Co. is quickly becoming my favorite mineral dealer. Not because his assortment is better or deeper than any other dealer but because he takes a minute to educate. A good example would be the current auction offering.

———————-

Starting a new theme auction on prismatic crystal shapes – ie, crystals with a long c axis – is starting today. There are over30 items at. More may show up before the day is over:
http://auction2.mineral-auctions.com

As for prismatic crystals, just think of them as the fashion models or basketball players of the mineral world. Long, slender crystals that draw the eye or extend past the crowd.

A prismatic crystal form is defined as one having faces parallel to the axis, esp. the vertical axis.

Several of my favorite minerals (elbaite, beryl, linarite, azurite) can form crystals like this. Interestingly enough, beryl tends to have varieties with much different proportions – long and slender versus short and wide.

Usually, emeralds, red beryls, aquamarines, and heliodors take on prismatic shapes.
Goshenites and morganites tend to have short C axes and resemble thick flattened hexagon.
On the other hand, it is fairly uncommon to see short, wide elbaite crystals.