Dont use them anymore, there in the hunt to rip people off.
Sent load of gold in, 2 peices of which bought within the last 6 months from a reputable shop stamped at 22ct. Sent in over 10 peices of 18 to 22ct gold to them. They said its all 18ct. including the 2 bits guaranteed to be 22ct. Went to a local gold specialist and they also tested it at 22ct.