Historically, gem materials of a biological origin were called organic. The term organic can be confusing as a definition by itself because of its use as a clarifying word for natural substance that has had no additional chemical intervention. 

To clarify the term for the jewelry trade, CIBJO, the World Jewelry Confederation created the term "biogenic" at the Pearl Commission in Armenia in 2016. This new expression would refer to any gem material created from a living organism as "biogenic". Organic could still be used but it would refer to biogenic material that were essentially composed of organic matter as in a chemical definition. These would include tortoise shell, black coral, horn, copal, and importantly pearls and precious corals.

When you hear biogenic as a description of pearls, you will know that it is a more definitive way of qualifying these beautiful organic gems.