Definitional Disclaimer

Terms used in this website are general in nature.

One question you might have is:  What is agate/nodule/geode? One answer is: “According to sample, design or structure of the agate layer, trade and science have given various names to the agates.” Walter Shumann, in Gemstones of the World, page 134, describes and depicts various types and names for agate. Since agate is normally considered chalcedony (Shumann, pages 126, 134), but not all chalcedony is agate, disputes arise over what is and is not agate versus chalcedony versus jasper versus japagate (page 163, Gem Trails of Texas, by Brad L. Cross).

So, this website uses the term “agate” generically to describe all of the above. I define nodules as voids or gas bubbles in volcanic lava that have filled completely with silica or other mineralization, often forming agate and/or crystalline structures. I define geodes as a nodule that has not completely filled with material.

In addition, please note that all of the stones depicted on this website are from the “Carver” find.