Gemology › Forums › Gemology 2 topics and 8 replies Last updated by Alan Balmer 10 months, 3 weeks ago Viewing 2 topics - 1 through 2 (of 2 total) Topic Voices Posts Last Post Gem Information 3 7 Alan Balmer 10 months, 3 weeks ago Light Physics 3 3 Justin Prim 4 years, 1 month ago Viewing 2 topics - 1 through 2 (of 2 total) You must be logged in to create new topics.