Chrome Pyrope Garnets

[zeolite]

Chrome pyrope garnets, sometimes know as “anthill” garnets, have the most intense hues in the garnet world. They are called chrome because the coloring agent is chromium, the same element that gives ruby its intense color. The red in the picture is as accurate as I can get on a monitor, but the actual gem is pure red (not orangy red) as in this picture.

This red gem was in a sense, created, rather than just purchased. I searched through over 500 crystals, trying to find the lightest toned crystal in that lot. The crystal was presented to a top cutter, with not the normal goal of cutting the largest size, but to be cut as thin and as shallow as possible, yet keep good optics and no window. This was requested to increase brilliance.

Rubies differ from garnets in at least one important way. When a red garnet has intense color, its tone is so dark it is almost black. A ruby will show intense color saturation, yet show much better brilliance than a garnet. The ruby shows both intensity AND brilliance.

I showed the red chrome pyrope garnet to a wholesale gem dealer who was a ruby specialist. He did not recognize that the gem I showed to him was a garnet! The combination of intense color and brilliance erased any thought of it being anything but a ruby.

 

[Pandora II]

Beautiful colour! I'm not surprised they didn't know it was a garnet - sad how under-rated they are as a species. Although on the plus side, I can actually afford to buy them!

I know in the past that cabochons were often hollowed out to make the most of the colour and prevent them looking as dark as they would if they were solid.

Is this practice still going? I'd love to see one someday.

 

[Richard Sherwood]

Wow. Killer garnet. Very, very nice hue.

 

[Richard M.]

The name "anthill" garnet refers to the chrome pyropes found in the U.S. in AZ, NM and UT primarily, where Native Americans located deposits by inspecting anthills to see if any garnets had been brought to the surface. Chromiferous pyropes are found all around the world, often as important geological indicators of diamond-bearing Kimberlite pipes.

Unfortunately they are usually quite dark in tone, with only small cut stones of 4 to 5 mm. displaying the best red color. Larger stones quickly become very dark unless they''re deliberately windowed, as in the case of zeolite''s example. They often have lots of inclusions, too. Some years back I found a source for larger rough and spent a lot of time trying various cutting angles to show off both color and brilliance without much success.

The hollowed-out cabochons Pandora mentioned were sold as "carbuncles." I saw some a long time ago when a dealer was selling off old stock cut in Germany but didn''t buy any. The name "carbuncle" goes back to antiquity. Its meaning isn''t clear. The Greeks referred to "anthrax" which, translated into Latin, is "carbuncle." Pliny referred to their source as "troglodytes" (cave dwellers) who got them from Ethiopia.

In Rouse''s book "Garnet" he speculates they could have been transported from southern India to trading centers in East Africa. So-called "Carthaginian carbuncles" were described as smaller in size and darker in tone than the others, with a purple hue in shadow and flame red in transmitted sunlight. He thinks they could have been some type of pyrope-almandine garnet or even red corundum.
Richard M.

 

[marcy]

Gorgeous! I love garnets.

 

[Selkie]

Amazing stone! That reminds me I have a lovely pair of small anthill garnets to set soon.

Richard, "carbuncle" is such an unfortunate name! Fitting, I suppose, for a red, blister-shaped gem, but not very appealing. I''m sure, were they being marketed today, someone would have come up with something more aesthetically pleasing.