In the 18th century, which metal was often thrown into the sea to avoid counterfeiting?

"It... commonly contains... platinum..."???

Ali *Regulus* Mirza, They are referring to the ore in which it is naturally found. It could be stated better.

Ali. Please complete your question. Most people can see it is just a statement at the moment. You have clearly by mistake missed a few words that would change it into a question. Then the " question mark" at the end would be correct.