Does anyone know whether it is OK to send a student/associate of
mine who doesn't have a resale number to the gem show to buy on my
behalf, using my resale certificate?
Noel, ethics isn't really a problem here, and neither, really are
legalities. You send your student with your tax number, and in
essence, you're representing that he/she is buying on your behalf.
Nothing wrong with that, so long as the show will let them in (not
all will). However, understand that one primary reason for the tax
number stuff is so that dealers don't have to worry about sales tax
liability themselves. That means buyers are responsible for filing
and paying any sales or use tax that may be due, now or eventually,
on the purchases. In this case, since purchases are being made with
YOUR number, you're essentially liable for taking care of the taxes.
Properly, your student would show up with the reciepts, which would
be given to you. You'd then write a reciept to the student showing
that sale from your inventory at the same cost (or make a commission
if you like), with any sales due added on, which the student would
then pay you. You'd then file that as a sale with your sales tax
return. Since the purchase price and sales price are the same,
you'd not generate income on which tax would be due, though in a few
instances, there are business taxes due on gross reciepts, in which
case that would impact you.
As to ethics, the ethical principal of wholesale shows is that
professionals don't like to find their own customers buying their
gems at the same places they do. This makes it impossible to add a
markup and compete, if the dealers will sell to anyone. But in this
case, your student is arguably working on the wholesale side of that
equation, or training to do so, so I see no problem with this.
Each show, however, has it's own requirements for who they'll let
in, and what proofs are needed. Some shows require advance
registration, as well as total proof that the actual individual is in
the business actually served by the show (so someone with a
restaurant supply business can't come buy their gems at wholesale
too, since they're really a retail gem buyer), some even want photos
of the store front, I think. The big shows for finished jewelery
are often this way.
Other shows are more lax, mostly covering their butts with the
various tax authorities. The GLW gem shows come to mind as an
example of such, or at least they used to be quite casual about it...