I have been fascinated by gemstone ever since I studied at the National Institute of Gemmology in Paris. First because I love their colours and because they cover the whole rainbow range, from transparent to opaque. Men can try all they want I don't see how we could ever reproduce the different spark of each natural stone.
The other endearing point about gems is that you can trace part of its life just by looking through it. The crystals grow very slowly, and like us, sometimes the external elements disturb their cycle, as an earthquake create some gaping holes in the stone. Other inclusions adorn the stone advantage, such as the famous butterfly wing of the emerald that looks like an organized heap of dewdrops.
Also when it grows, it absorb elements around, that we can identify after the stone is cut, and trace back when it came from.
All the stones I use in my jewellery are natural stones. I use a very large variety of stones. I buy some on famous market in Thailand every two years and find other on Bijorhca Fair in Paris. Some stones are more difficult to find, especially the raw stones, but nowadays, with enough research and an internet connection, you can find everything !