A reseller of equipment or material must mark up all expenses
including freight or they will lose profit margin. Once you decide
your profit margin, the amount you need to run your business, you
mark up all costs by that amount. If you don't, the profit margin
drops. Eventually you go out of business.
I am a big proponent of buying locally unless whatever you need is
not available locally. If you assume that local suppliers are out to
cheat you by over charging for their material, they can assume the
same thing of you when you add profit for something as nebulous as
"one of a kind, and made by an artist" to your work. People at Rio
and in Germany are not likely to buy your work. My point is, buy
from the people that are likely to buy from you and don't assume that
because they are a supplier that they don't want the same standard of
iving that you do. Give them their profit and and they will give you
I am not actively selling jewelry, but I do work in retail and the
principles are all the same.