In my current gemological studies, I learned that gemstones possess
two separate durability components, hardness and toughness. Hardness
is the stones resistance to scratching, while toughness is its
resistance to chipping, breaking or cracking. Diamond is a good
example. Diamond is the hardness known natural stone and yet it is
rated only “good” for toughness. As I have studied, Jade is tougher
There has been a discussion recently on the wearability of gemstones.
Diamond, Corundum and Tourmaline are the stones mentioned. For
reference, here is a list of some gemstones with their respective
hardness and toughness ratings.
Diamond 10 Good
Corundum 9 Excellent
Topaz 8 Poor
Tourmaline 7.5 Fair
Jade 7 Excellent
Opal 6 Very Poor
Now, I realize that numbers from a lab and performance in everyday
life can be two different things. For that very reason I am writing
this inquiry. When faceted edges are abraded, it is the wearing away
and chipping of these edges that produces this effect. It seems to
me that toughness plays a greater part in this effect than hardness.
From the toughness ratings for the stones listed, it appears that
Corundum and Jade would resist the everyday abuses of wear better
than the others, even better than Diamond. However, from previous
discussions, the very opposite may be true. Which is correct from a
I am calling upon all the experience out there to answer this
question. Experience is the most important ingredient of the
professional; an ingredient I lack. I consider myself fortunate to
be able to have a group like Orchid to learn from. Thank you.