GUERILLA GEMOLOGY- What is it?

[Richard Sherwood]

Nothing more than front line, practical gemology that’s good for the layperson and the professional alike. Gemology where the rubber hits the road, so to speak, along with examples of the day-to-day challenges that hits both the professional and the consumer as they navigate through “the gemstone jungle”.

[Edited after being moved]

 

[Garry H (Cut Nut)]

GG tip - when checking a colored stone for natural / synthetic.
1. If it is exactly 7x 5mm, 8x6mm, 9x7mm etc then assume it is synthetic till otherwise proven natural.

2. Check the faceting - if it is the style used on synthetiscs then it probably is a syn.

3. Always do the simplest quickest definitive test first. eg i use an old heat transmission tester to detect sapphire / ruby because it is the second best conductor of heat. Rules out garnet, GTD's, tourmaline and spinel etc and takes 3 seconds.

 

[Hest88]

Looking forward to it Richard. I love hearing about how this all works in the real world.

 

[Richard Sherwood]

Good tips, Garry. I especially liked the heat transmission tip.

 

[Richard Sherwood]

Heh heh heh...

Now THAT'S what you call real guerilla gemology, eh Furthermore?

 

[codex57]

Hahaha, this thread is great

 

[Garry H (Cut Nut)]

I found this image from exz......com of Rich at work.

 

[Richard Sherwood]

Looks like you caught me on a good day, there.

 

[codex57]

Since you guys still check this thread, any more interesting stories? This stuff is great.

 

[Garry H (Cut Nut)]

The top lip serves 2 functions

1. it quivers when we do not get our way
2. it is the most heat sensitve part of the body (that you may legally expose)

Put a diamond imitation in a setting or tweezers on your top lip and it will not feel as cold as a diamond.

(reason - diamond is the best conductor of heat full stop. next best is corundum - ruby and sapp - but I do not know if you could tell them apart?)

 

[meredithcute]

I'm an 85 gia grad also. I'm curious about the rarity factor of stones over one carat-cut. Seems I remember something about only one in every 100,000 stones is over one carat. Again, to clarify, cut gem quality. Is this correct? And if so, what are the factors to determine two carat, three, and so on. Is there any semi-accurate formula to use? Thanks much.

 

[Richard Sherwood]

I''d be curious as to those figures myself. Sounds like something which DeBeers would have access to.

I''ll keep my eyes open.

 

[meredithcute]

Thanks a lot for the answer. If you find anything out, please post it up!

 

[Garry H (Cut Nut)]

The argyle mine has an average of .08ct deeply etched rough - 1 or 2 polished stones of .02ct.

This distribution charts for diamonds drop away very quickly as size increases.

John Chapman is the man to answer this question.