barbara beardsley wrote:
I have been investing (as my finances allow in silver and gold. I've read
that precious metals are weighed in troy weight.

Yes, if it is in ounces, it will be troy ounces.
Silver and gold are also sold in grams and kilograms.

So when someone has a 1 lb.
silver bar to sell, thats a troy lb, isn't it?

The troy pound (12 troy ounces) has not been in normal use
since the 19th century, but if someone does specify a pound
of precious metal it will be a troy pound. Note that a pound troy
is less than a pound avoirdupois even though an ounce troy is
larger than an ounce avoirdupois.

Avoirdupois pound = 16 avoirdupois ounces
Troy pound = 12 troy ounces

Avoirdupois Pound 7000 grains 453.59 grams
Troy Pound 5760 grains 373.24 grams
Troy Ounce 480 grains 31.1 grams
Avoirdupois Ounce 437.5 grains 28.35 grams

(grains are exact, gram equivalents are approximate)

Some bars are just marked
10.20 oz, so thats troy ounces? Do they ever go by the avoirdupois(sp)
weight?

That would be really confusing. The convention is that the weight
of precious metals is either troy or metric and never avoirdupois.

I'm assuming all the spot silver/gold prices are measured in troy
ounces?

Yes, either troy or metric.

Peter.
--