Diamonds And Precious Stones

Where can I advice from an expert on precious stones, diamonds specifically?
I have a few questions for an expert in precious stones, diamonds specifically. I'm not looking to buy or any price. My questions are more focused on physical properties and characteristics of diamonds.
A gemologist from GIA must be able to help you (or a similar Certification Association). Look them up in the phonebook. Yes, they are sellers. However, they also have little knowledge of stones.
Double Circle 14k Gold Diamonds & Precious Stones Motion Ring FL-833