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Is there such a thing as a definitive answer for hardness & specific density?

0 votes

I am attempting to write a series of articles for our website (we sell semi-precious beads) but I am a little puzzled by finding differing values on various sites for characteristics that I had assumed would be standard. To give a small example, Tiger Eye. The hardness (Mohs) on three sites was given as follows:

A: 6.5 - 7 B: 5.5 - 6 C: 7

And the specific density was given as:

A: 2.58 - 2.64 B: 2.64 - 2.71 C: 2.63 - 2.65

As you can see, there is quite a range in both values and I have no idea which is the 'correct' one to use.

Can they all be right (possibly variations in the stone) or is there a definitive source that could give me the actual values?


asked Sep 14, 2014 by The Beadster (120 points)

2 Answers

0 votes

Tiger's Eye is a form of quartz and therefore has the same properties as quartz. Hardness of quartz is 7. However, impurities may slightly less its hardness, though I have found it to be closer to 7. Specific gravity of quartz generally ranges from 2.6 - 2.7, and tiger's eye will fit within this range.

answered Sep 15, 2014 by hershel (52,820 points)

Thanks Hershel for taking the time to answer.

Do I take it from your answer that there is no 'definitive' site but that each mineralogical site will have their own values based upon their own members experience?

Or am I obsessing about wanting to publish the most accurate figures for these two values that I can find?

0 votes

When minerals are pure without impurities, they will will have strict defined properties. However, this site takes into account impurities which often accounts for a a wider range of values.

answered Sep 28, 2014 by hershel (52,820 points)