This is a pic of a collar/choker I drew. Gold choker with a ruby heart lock, that really works. I put the hole for the key in the center so the heart opens up and the choker comes off that way. And has a matching ruby and gold key, made to look like the old fashioned keys. I put Emerald and Saphire on the side, because not everyone likes Ruby like I do. I'm not sure on the size yet, the gold part would have to be smaller for it to look more fem. and not be so bulky. The heart about quarter size but no bigger than a half dollar. And the key to be whatever size it needs to fit the necklace, and the end of the key that has the ruby on it, to be the same size as the heart on the necklace. The key would be a little harder to make since its a cut out heart, but I don't think its impossible.