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Diamond Sorting


#1

I have maybe 800 or so small round diamonds from .0025 carat to.02
carat.

They are all mixed together as I have been collecting them for years
from buying scrap gold rings. I would like to sort them according to
size. How would you do ite I see that the major supply houses sell
diamond sieves.

Stuller has one for $115.39. Is this what I need to purchase or do
you have a better suggestion?

Thanks in advance.
Dale Pavatte


#2

I have a set of diamond sieves I purchased from Stuller for the same
reason.

A sieve makes short work of rough sorting a large number of mixed
size diamonds.


#3

Make your own sieves. 0.02 carats is 1.7mm and 0.025 is 0.7mm. This
corresponds to mesh sizes 12 through 18. Glue a pvc pipe slice (or
any other slice of rigid 1-2" diameter tubing) on a piece of mesh.

Amazon.com has diamond sorters for as low as $40.


#4

Dale- We use an antique brass sieve. Love it. We only use it about
once a year but it sure comes in handy when sifting though melle. You
could make your own I suppose by drilling out sheets of copper or
brass.

Have fun and make lots of jewelry

Jo Haemer
timothywgreen.com


#5

Dale,

I’m all for making your own BUT-once sorted what are you planning to
do with the melee? Most diamond buyers aren’t interested in melee.
Pawn shops won’t take it. Even if the stones are above SI-I2 in
quality who would use them and for what? In fact just yesterday I
sold a certified quarter carat + (“heavy quarter”) IF-V V S (when a
diamond is a quarter -from a “light quarter” up to almost a half
carat- it is Rappaport classed in the Internally Flawless to Very
Very Slightly Included grade) of D/E colour as two CG’s couldn’t
agree on the exact “colourless” colour grade for half the Rapp as
there isn’t much call for custom work under a carat, and art jewelers
don’t generally get commissions under a half carat. melee is even
harder to get rid of as replacement benches often have thousands
from take outs themselves. So before investing over a hundred bucks
before postage and handling, have a buyer lined up.

You may want to make a sieve in any case. Drilling in a brass sheet
works well if you are accurate in matching the drill sizes to the
measurement of the melee in millimetres and use a drill press (don’t
try to do it by hand or the sheet will spin with small twist drills
or even ball burs - and remember to keep the bits well oiled with
wintergreen oil to cool and lubricate or they will anneal going
through brass sheet).I think one poster suggested cutting pvc pipe
and attaching it to mesh- matching the mesh with melee dimensions
could prove daunting at least ! Call around if you know some bench
jewelers in your area Someone may lend you a set/one for a day or so
to sort them or give you an extra they no longer need or use. I
wouldn’t invest more than a hundred in something you may use once
every few years as once you have them sorted simply mark the diamond
papers with the dimension across the girdle/ top of the stone and
using a standard brass Levinger’s gauge or even better a digital
gauge sort subsequent melee using the measurements from sieving as a
standard if you have returned a borrowed sieve… rer