About the Agate Lexicon
The Agate Lexicon and glossary of amorphous and cryptocrystalline silica gems have been designed to be used in conjunction with the Agate Bibliography, which was compiled to be used by researchers, hobbyists, historians, lapidaries and other individuals which have an interest in these stones. Numerous localities are listed here but this does not imply that the sites are available for collectors or collecting. Many of the sites are historic, depleted, are on private property or are protected by legal leases or claims and some are now on protected sites such as parks, nature preserves, or historic areas. Wherever possible, stratigraphic details are listed, but the user must always refer back to the original citations. Map information has been derived from 7.5' x 7.5' topographic maps issued by the U.S. Geological Survey (USGS) and latitude and longitude have been derived mostly from Geographic Names Information System of the USGS.
Authors should not cite the Agate Bibliography or Agate Lexicon as a source in their published or unpublished works but should cite only those publications listed therein.
Named varieties of agates, jaspers, etc., have created special problems for both scientific researchers and historians. We have recognized at least two different usages of names. Some names appear to have geologic / historic validity, as they were described along with the lithology / geography of a region. Some names were introduced simply as trade names to boost sales of gem dealers. In the former case, the name will be followed by appropriate literary citation as to who first used the name and in what context. In the latter case, an advertisement (abbreviated adv.) is the first published record or public notice. We have tried to find the earliest citation in either case and the user should keep in mind that older citations unknown to us may exist. Advertisements are not cited to generate business but to simply give a historic source; many of the firms appearing in the citations are indeed no longer in existence.
Cited materials are generally only from accessible sources such as professional journals, magazines, hobbyist journals, open file reports of government agencies, newspapers, etc. Bulletins issued by local clubs and societies are generally not cited with the exception of those special publications that were actually made for public distribution.
Wherever possible, imagery of one or more specimens of named agate varieties, structures, patterns, etc. are provided. Images have been provided by several sources and are not to be utilized in other pages without the consent of the image owner.