I’m no expert,so could have got it all wrong,and yes,I wondered if it was dipped,but I did the unthinkable and scratched it to find the brass,but if it’s a coating it’s pretty thick.Maybe someone can put me right,in which case I still love the necklace whatever it’s made of,but I tried the scratch test,which Pearlescence mentioned being the test until recently used by the assaying office for hall marking.Quite a few bullion and gold buying sites also give the same test as a faiirly conclusive proof of gold.You scrape your metal across a piece of unglazed ceramic,the back of a plate,or tile.As gold is comparatively soft,it will leave a gold streak,base metals will leave a black one.My wedding ring streaked gold( my husband would have been in deep poo if it hadn’t) The brass key for our grandmother clock was black,and my necklace was the same colour as my wedding ring.What a happy way to spend a wet afternoon...There could well be another explanation,maybe the test isn’t conclusive,but it all add twists and turns to my humble necklaces story.7