Books are the training weights of the mind.  Epictetus, ca. 50–135 CE

Brush, ink, paper and ink stone are known in China as the “four treasures.” Long ago, the Chinese recognized that these simple tools were the most important invention of all, because they allow human beings to communicate ideas remotely, even beyond the grave, granting our species a form of immortality unlike any other. Thus we have christened the Lotus Gemology reference database after the most important human tools of all time.

At Lotus Gemology, we believe knowledge is the common property of all humankind. Towards that goal, we are making our internal reference database—created with thousands of hours of work over a period of nearly four decades—available free of charge. It is our way of giving back to those who have come before us, as well as providing tools to researchers to push gemology ahead.

The Lotus Gemology Four Treasures database contains thousands of references relating to gems, gemology and mineralogy. It is particularly strong in citations relating to corundum (ruby, sapphire), jade, emerald, spinel, color science, and Arabic-language gemology.

Got a reference you’d like to see included? Feel free to send it to us for consideration. Find a mistake? Again, let us know so we can correct the database.

8495 references total

Basic Reference Search

Advanced Search Options

Search Notes

  • Click on any cover image to view a larger version; note that covers may not be the exact issue number/edition of the reference in question
  • RWHL, JLEL, LTL - Copy or original in the Richard W. Hughes, John L. Emmett and/or Lisbet Thoresen Libraries
  • *,** - References of Particular Merit

Reference Types

  • Books (Includes Ancient Text, Book, Book Sections, Catalog, Conference Proceedings, Dictionary, Edited Books, Electronic Books, Electronic Book Section, Encyclopedia, Manuscript, Pamphlet, Report, Thesis, Unpublished Work)
  • Articles (Includes Blog, Conference Papers, Electronic Articles, Journal Articles, Magazine Articles, Newspaper Articles, Patents, Press Releases, Web Pages)
  • Multimedia (Includes Audiovisual Material, Film or Broadcast, Podcast)
  • Other (Computer Program, Discussion Forum, Map, Personal Communication)

Hidden Treasures | Lotus Gemology's Special Literature Guides

For those who wish to explore the literature of gems further, we recommend the following:

Key Reference Books

Below are listed the most important reference books for the literature on gems, minerals, jewelry and allied fields. To access a full list with cover images and abstracts, just do a general search on "bibliography".