A Grain of Sand is a beading supplier which hosts a beading resource site titled the AGOS Bead University. It is a site worth bookmarking as there is a list of bead terms, definitions of gemstones, and a glossary of findings. These lists are illustrated with photographs which makes them particularly useful.
There is a good section on vintage beads and some interesting articles on pearls. For instance in the section on vintage beads there are informative articles on Rhinestones, bakelite, and dating Swarovski Crystal. There is also a very useful article and chart on vintage Seed bead sizing and seed bead terms.
To top it off the site houses a customer gallery which provides lots of eye candy and inspiration. So make a cuppa browse the articles and visit the gallery. I am sure you will enjoy it.