I inherited these gold and crystal grapes along with a bunch of other items some of are which are valuable and others are just pretty or fun. I want to know if they are swaroski crystals, and real gold. I didn't see a mark but i don't really know what i am looking for or where to look? They are very heavy and sit on a mirror. Swarvoski or not i would like to know more about them. Maker, Age, Value and how to care for and clean them them. Thank you for any info or help you can provide.