Second hand silver

I bought two generous size pieces of reticulated silver, interesting
but very overheated, I think. When I cut a sliver to make a ring it
cracked while bending. Don’t think it can be annealed.

I also have two pieces of 20 gauge silver 6"x18", marked “20-25%SF”.
What’s "SF"e?

Thanks.
Cathe Linton

I also have two pieces of 20 gauge silver 6"x18", marked
"20-25%SF". What's "SF"e? 

Possibly it is indicating that it is “Silver Filled” with a 20-25%
weight fraction silver. There is no current standard for marking
Silver Filled items in the US so that may be what they are trying to
say.

James Binnion
James Binnion Metal Arts

SF = “silver filled” the percentage gives the amount of silver used
to coat the copper core.

John