Well, Jocelyn, I hope you are sitting down as you read this. Since I
didn’t want to use imaginary numbers, I got a piece of 18 ga. silver
sheet, 1 3/4" x 1 1/4" - about the weight of 2 crosses saw pierced, I
That piece weighed 9.6 pennyweights (1 troy oz. = 20 pennyweights or
Dwt.). Silver spot on Friday was $7.19, dividing by 20 is $.44/dwt.
Multiply by the weight of 9.6 and we get a cost of $4.22.
Spot gold was $420.90 - call it 421.
Doing the same thing, converting to 14kt. (spot x .585), we get
You can estimate the weight of a piece in different metals by the
ratio of their specific gravities, so 14k will weight 1.276 heavier
than silver, making 9.6 dwts. into 12.24 dwts. 14k for the same
piece. So, 12.24 dwt. times $12.30 =$150.55 for that same piece of
Now the sitting down part - If that sheet is platinum, it will weigh
almost exactly twice as much, spot is $879, and there is no 14kt.
platinum, it’s just spot. So: 9.6 dwt. x 2 = 19.2 dwt. $879/oz.
/20 = $45/dwt. 19.2 dwt. x $45 = $864, just for that piece of sheet
Lest you think there is some flaw in my calculations, let me assure
you that there is not - bearing in mind that it’s only an estimate.
If anything it will probably be more. If you clipped off a wooden
matchhead, and turned it into platinum, it would be worth about $20.
Each stroke of a sawblade is worth a quarter.
I do not mean to put you off - just be aware of the realities.
Then, that piece of sheet is only one cross, my thinking being that
the scrap could be recycled into the second cross. OK, the melting
point of silver is 1760 deg. F. The melting point of iron is 2802
deg. F, and most steels run 300 - 500 deg hotter. The melting point
of platinum is 3224, but since you will be using 10% iridium plat.
(Iridium = 4449 deg. F), it will be more like 3800 deg.
And, like all metals, you need to superheat it (“till the surface is
swimming”). You need a porcelain crucible, good goggles, and you
essentially have a miniature Sun glowing on your workbench. I think
of silver, gold, copper, brass and bronze as being cousins - anybody
who can work one can work the others with a minimal learning curve.
Platinum is not the same - Yes, you use the same tools, but in
different ways. I quit using a fine file, because it loads up and
puts gouges in the finish. I use a roughing file, and then sand it
from there - very different from silver.
However, and the point of this letter - if you are reasonably
skilled, with perhaps a little coaching, you probably could do a fair
job with the craftsman part of it. It is the realities of the metals
market that many people haven’t seen yet.