Connectors from UPS's?

I have been parting down UPS's for a while and selling the innards to my
local scrap yard. I have been cutting off the connectors that look like the
one in the picture and they have two silver looking ends on the wire. Anyone
know if they are made with silver and what their composition might be?



I just smash the plastic connectors and pull out the silvery connector ends.
Should I continue to keep doing this or just sell the whole connection with
the copper wire I harvest from the UPS's?

Thanks!