He has a chain [which is made of gold].
The sentence has two clauses: a main clause (italicised) and a subordinate clause (bracketed) embedded within it, each having its own subject and predicate. In the main clause, he is subject and has a chain which is made of gold is predicate. In the subordinate clause, which is subject and is made of gold is predicate.
I have seen the above explanation of clause in an English forum. Is it correct? Can I also say that He has a chain is also a clause with He as its subject and has a chain as its predicate?