todds rough diamonds are a step above industrial diamond material in
that he chooses specific shapes (octahedral, cubic, etc. and they
are somewhat more distinctly coloured than industrial diamond lots
that are considerably cheaper and not selectable or “matched” in any
way. Good rough diamonds are generally three times the cost of
industrial diamonds for the same sizes (relatively the same).
Industrial diamonds are very opaque and sometimes have visible
inclusions on the faces of the crystals- good rough has much more
transparency and can be had with perfect, natural faces (no rutile
needles, etc. obvious on the crystals). He sometimes does use med.
size industrial crystals and cuts them to a basically uniform size or
shape to end up with the equivalent of a .25 diamond cube but even
then they are “high grade”- if you want to call it that, for
industrial material. there are also S. American “fruit salad” rough
diamonds that are translucent to almost transparent that are far
above industrial grades but generally smaller than the largest
industrial material available yet still at a reasonable price (even
some industrial material can run on the pricey side). I suppose I
shouldn’t have used Todd Reed as an example, I use a fair amount of
rough diamond crystals in some collections and the material I buy is
translucent with inclusions that would be equivalent to a SI1-2
graded faceted diamond. It all comes down to what amount you want to
spend for what appearance you need. Industrial material is fine if
you just want to say it is a diamond, if you want to use crystals for
their shape or colour, i find industrial diamond too opaque and
imperfect for my designs,; even if i’m going to shape a stone to any
degree I want some natural colour to it,(even if its grey or silver,
or pale green) and don’t want to have a spot of included material on
a visible face of the crystal. the ring below is a good example of
what I mean by a transparent rough diamond crystal - this is a 15th
century find shown on BBC’s Antique’s Roadshow. I couldn’t find an
image with a view from above but the difference in clarity is
tremendous over industrial material.(the ring probably cast in
cuttlefish bone originally is 24 kt gold and the engraving work quite
nice also!)…rer