Cohen & O'Neill Jewelers Inc

I was looking to have a small stone set either in a new ring or one that I have. I decided to alter the one I had that means I would have to buy a.10 yes .10 diamond. He was going to charge me 200 for the diamond, most places were going to charge me about 100 for the same stone and online even less. I told him this he said pretty much oh well it is what it is, he proceeded to tell me he does enough business not to worry about my sale or not. Very rude, very cocky and I will never tell anyone of this place. He also likes to bad mouth local jewelers in the area saying, and I quote 'they lie about the stones and give you cheap diamonds'