Moh Scale

[brazen_irish_hussy]

I am trying to pick a stone for my engagement ring but not a diamond. I was wondering hardnesses are ok and which are too soft. Also, are there other thigs like cleaveges that are important to a stone''s strength. I know bezels protect stones better, but I am looking for stones that may not need to much protection.

 

[Kismet]

This article at ACstones.com is pretty helpful.

 

[movie zombie]

welcome to the world of color!

depends on whether its going to be worn 24/7, or if it will be taken off at home and not worn doing the dishes, cleaning house, gardening, etc.

the higher the MOH, the better....accept emerald [that cleavage issue you mentioned] is a bit touch and will shatter despite the high MOH number.

bezeling will help but some don''t like the look of a bezel. avoid sharp points, like marquis and pear points, if a bezel isn''t desired.

my e-ring in my avatar is a spessartite garnet with a MOH of about 7.5. i don''t wear it 24/7. Mine has her spessartite wrapped with a halo of diamonds. some have gone with tourmaline. much of it depends on what look you want and what you''re willing to spend. high quality sapphire is going to cost you as will ruby.

personally, if its going to get some wear and tear, i wouldn''t go under a MOH of 7. but learn as much as you can about individual stones. oh, and spinel is an option!

however, good quality color stones can be as pricey....and in some cases....more than diamond.

movie zombie

 

[brazen_irish_hussy]

What about toughness and stability? I know jade is much tougher than diamonds for example even thoug it is not as hard. Does anyone have a chart of the toughness of stones? Also, stability. For example, I know opals should be soaked in water when they live in dry climates. Anything else?

 

[Richard M.]

Date: 8/4/2006 12:34:21 AM
Author: brazen_irish_hussy
What about toughness and stability? I know jade is much tougher than diamonds for example even thoug it is not as hard. Does anyone have a chart of the toughness of stones? Also, stability. For example, I know opals should be soaked in water when they live in dry climates. Anything else?

All great points. This site: http://www.bfbrogan.com/col.html rates major gems for both hardness and toughness. As for stability, opal is one of the few gems of concern. You have to be aware of the opal source. Australian and Brazilian opals are generally the most stable. The least stable are opals from Mexico, Indonesia and certain areas of the U.S. like northern Nevada and Idaho.

Opals need to keep their internal moisture in balance and don''t like ultra-low-humidity environments like deserts and bank vaults (moisture damages paper wills and stock certificates so bank vaults are dehumidified).

Books are still the best sources of this kind of information. The classic "Handbook of Gem Identification" by Richard T. Liddicoat, available from the GIA Bookstore, has appendices dealing with the most important gemstone properties. So does Schumann''s classic "Gemstones of the World," which also has excellent photographs.

Richard M.

 

[Barbara]

Date: 8/3/2006 8:09:06 PM
Author:brazen_irish_hussy
I am trying to pick a stone for my engagement ring but not a diamond. I was wondering hardnesses are ok and which are too soft. Also, are there other thigs like cleaveges that are important to a stone''s strength. I know bezels protect stones better, but I am looking for stones that may not need to much protection.

I have been asked this question many times, so over the years I have had to think carefully about it. Considering that an engagement ring is going to worn 24/7/365 the possibilities in colored stones are limited. (For gently worn or occasional wear rings, many other doors open up, though). There are three aspects of gem durability: hardness (MOHS), toughness, and stability. In hardness (ability to resist scratching), the e-ring gem should be at least 8 which already limits the colored stone choices. In toughness (the ability to resist chipping and breaking) it should be good or better. In stability, the ability to resist changes due to temperature, light and chemicals, the gem should be stable. Taking all those factors together, we are left with spinel (on the low side of hardness, with some care still required), chrysoberyl (which is great if you want pastel yellows and greenish yellows-- or a cat''seye), and sapphires (careful with rubies, though, as they are sometimes included enough to diminsh their hardness/toughness). Happily, sapphires come in a rainbow of colors.

You might ask "what about topaz?" at hardness 8? It''s not a good choice due to its poor toughness.

Colored stones, as much as I love them, except for the ones mentioned above, are better for occasional wear rings and bracelets. We can go crazy with brooches, earrings and pendants though. The picture attached is of a red spinel ring I wear frequently, it is protectively set. (Well I thought I attached it, but ? I get an error message -- sorry, newbie syndrome)

Barbara

 

[movie zombie]

love the ring, Barbara! i''ve either seen it somewhere else or one very very similar!

movie zombie

 

[asscherisme]

I think ruby and sapphire are safe choices. I own a ruby ring and a sapphire ring. They are not engagement rings but since I''m right handed and rotate them on my right hand, I researched hardness before I choose what colored stone to get. I like knowing the stones are durable. If you choose a ruby or sapphire and mount it in platinum, you have a nice durable ring with lots of possiblity for color and design!