Agates Lexicon

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ID Agate
1350Ice Agate, a milky chalcedony with inclusions of color-less quartz in matrix. Term developed by G. J. Bittell, Germany. The Mineralogist, v. 21, no. 9, p. 297.
1351Ice Blue Agate, Arizona, no description, adv., Arlene Dimick, Lapidary Journal, v. 14, no. 3, p. 291.
1352Ice Bone, Colorado/Utah? an agatized dinosaur bone that is white on the exterior with purple spider webbing in the interior, color illustration in Talbot (1978, p. 1260).
1353Iceland Agate, Iceland, Van Leunen (1945, p. 125) used the term for brownish and grayish obsidian from Iceland; Shipley (1971, p. 98) suggested it was an obsidian; and Frazier and Frazier (1988, p.73) used the term in this same sense. However, Harstad (1936, p. 141) citing Feuchtwanger, 1838 [not seen]) stated that ...the best agates are...those from Oberstein, Iceland, and Faroe Islands. Harstad further stated that he had seen agates from these localities.
1354Icicle Agate, California? Nevada?, no further information, adv., Gordon's, The Mineralogist, v. 15, no. 11, p. 607. Johnson (1978, p. 38) used the term without a description for material from near Blair Junction, Esmeralda County, Nevada.
1355Ida Jasper, Virginia, a red jasper with hematite spherules, see Livingston (1954, p. 4-6, 8).
1356Idaho Brown Lace Agate, adv., Tynsky's Gem Shop, Rocks and Minerals, v. 37, no. 3, 4, p. 219.
1357Idaho Foliated Agate, no description, no location, adv., Stardust Gem House, Lapidary Journal, v. 1, no. 2., back cover, outside.
1358Idaho Picture Rock, Idaho, volcanic tufa with jasper in beige-brown or rose red, adv., Arco Rock Shop, Lapidary Journal, v. 25, no. 1, p. 190.
1359Idaho Plume Agate, Idaho, adv., Stewarts Gem Shop, Earth Science, v. 13, no. 3, p. 107. ...beautiful plumes in many colors with clear background, adv., Smokey Mtn. Rock Shop, Lapidary Journal, v. 29, no. 3, p. 601.
1360Idaho Potato Agates, Idaho, agate nodules form Grouse Creek and Hog Creek according to adv., Stewart's Gem Shop, Lapiday Journal, v. 3, no. 5, p. 358. See also Beacon Hill nodules.
1361Idaho Potato Nodules, Idaho, agate patterns with red, green moss, occasional sagenite. Adv., Jim Mahlum, The Mineralogist, v. 20, no. 12, p. 461. ...fluoresce bluish green under S.W., adv., Indiana Lapidary Supply, Lapidary Journal, v. 15, no. 8, p. 111.
1362Idaho White Plume Agate, Idaho, no description, adv., The Agatique Shop, Lapidary Journal, v. 8, no. 4, p. 363.
1363Idaho Willow Creek Jasper, Idaho, synonym of Willow Creek Jasper which see. Term appeared in adv., LarryƆs Rocks & Gems, Lapidary Journal, v. 44, no. 11, p. 142.
1364Idaho Yellow Onyx, Idaho, an agate or jasper?, adv., Lowell W. Fields, Lapidary Journal, v. 30, no. 12, p. 2764.
1365Idar Agates, for Idar, Germany. Applies only to agates having been collected from this classic locality. Agates from many other sources have been cut and polished there and advertized as Idar (Idar-Oberstein) agates. adv., Martin L. Ehrmann, Rockefeller Center, Suite 2008, International Building, 630 5th Avenue, New York City. Shipley (1971, p. 98) suggested tha the discovery of these agates led to the establishment of the great lapidary centers of Idar and Oberstein.
1366Idar-Oberstein Agate, Germany, agate, onyx, sardonyx, adv., John M. Wise, Lapaidary Journal, v. 9, no. 4, p. 355. Gotze, Plotze, Fuchs and Habermann (1999, p. 152, 153) suggested that agates from this site formed in an andesite and examined them by electron paramagnetic resonance, cathodoluminescence and trace element content.
1367Imperial Chrysoprase, Australia, a chrysoprase of exceptionally fine color and translucency, adv., Bearden's, Lapidary Journal, v. 21, no. 10, p. 1238.
1368Imperial Green Agate, Mexico, ...variety of shades of green and occasional presence of white,...adv., Goodnow Gems U.S.A., Rock & Gem, v. 7, no. 8, p. 5.
1369Imperial green jasper, Mexico, shades of green, ...occasional presence of white, tan or brown or reddish colors, adv., Goodnow Gems U.S.A., Lapidary Journal, v. 31, no. 4, p. 883.
1370Imperial Jasper, Mexico, ...attractive green, pastels, adv., Goodnow Gems, U.S.A., 3415 Hayden Street, Amarillo, Texas 79109, Rock & Gem, v. 4, no. 6, p. 3. Fraser and Fraser (1989) stated it came in red and green varieties and I have observed both red and green imperial jasper for sale at shows. An advertizement by Rivera & Sons, (Lapidary Journal, v. 30, no. 12, p. 2816) suggests this material is from the state of Zacatecas.
1371Inchture, Perthshire, Scotland, historic locality that has yielded amygdaloidal agates from lavas of the Old Red Sandstone of Early Devonian Age; the site was recorded by Heddle (1901, p. 76) and was stated to contain ...the most delicate tints of lilac, flesh red and rose in grey-blue chalcedony. Macpherspon (1989, p. 19) also mentioned this site.
1372India Fern Agate, India, no description, adv., Ernest Meier, Lapidary Journal, v. 5, no. 5, p. 377.
1373India Green Moss Agate, India, adv., Merle's Rock Box, The Mineralogist, v. 26, no. 4,5, p. 137.
1374India Light Skin Agate, India, no description, adv., Quinn Mineral, Rock & Gem, v. 5, no. 8, p. 58.
1375India Moss Agate, India, adv., California House of Gems, Earth Science Digest, v. 7, no. 1, p. 40. ...fine lacy patterns of pink, lavender, red, tan, and green. Adv., Gemstone Shop, Lapidary Journal, v. 15, no. 1, p. 166.
1376India Picture Agate, India, a jasper?, no description, adv., Aleta's Rock Shop, Lapirary Journal, v. 30, no. 8, p. 1495.
1377Indian Agate, India, Shipley (1971) used the term to refer to Mocha Stone and Moss agate and this usage supports geographic implications since Mocha Stone and moss agate come from the same area in Rajpipla State (Bose, 1916).
1378Indian Agate, California, ...splashes of reds and yellows, Ferguson (1984, 922-931, 942, 943), color illustrations.
1379Indian Blanket Jasper? Oregon, no description, adv., E. H. and Nellie Combs, Lapidary Journal, v. 3, no. 6, p. 451.
1380Indian Chip Mines (Agate?/Jasper?), Ron Ochs Ranch, Oregon, name used without description by Eaton (1988, p. 63-65).
1381Indian Pass, California, site that Berkholz (1971, p. 78) reported to produce agatized wood and brecciated jasper. There are several sites with the name Indian Pass in Geographic Names Information system and the exact site has not yet been traced to a 7.5 minute topographic map.
1382Indian Green Tree Jasper, no locality (India?), no description, adv., Art by God, Lapidary Journal, v. 45, no. 5, p. 76.
1383Indian Picture Jasper, no locality, no description, trade name?, adv., Moyer Rock Shop, Rock & Gem, v. 5, no. 8, p. 12.
1384India Picture Rock, India, a jasper?, no description, adv., Aleta's Rock Shop, Lapidary Journal, v. 30, no. 10, p. 2376.
1385Indian Picture Rock, California, no description, Aleta's Rock Shop, Lapidary Journal, v. 33, no. 5, p. 1187. This may not be either an agate or a jasper, rkp.
1386Indian Quarry (Agate?,/Jasper?), McDonald Ranch, Oregon, name used without description by Eaton (1988, p. 63-65).
1387Indian sardonyx, a sardonyx in which layers of white, yellow, and warm red-browns predominated. Neverov, O., 1971, p. 52.
1388India Tree Agate, India, ...white base with green fern and tree designs, adv., Baylor Gem & Rock Shop, Lapidary Journal, v. 22, no. 4, p. 590
1389Indore, agate collecting locality in India, (Francis, 1983, p. 1980-1987).
1390Inferno Agate, Mexico, no description, adv., Gem Center U.S.A., Lapidary Journal, v. 18, no. 1, p. 131.
1391Inland, sub-variety of Lake Superior Agate, adv., Gem Exchange, The Mineralogist, v. 7, no. 2, p. 59
1392Iona, Argyllshire, Scotland, historic locality that has yielded agates that may have formed on Mull in basalts of Tertiary age; the site is noted by Heddle (1901, p. 76) as containing agates A...loose on the shores of Machrihanish Bay and Iona. Macpherson (1989, p. 19, 50, fig. 110) suggested this locality is still productive.
1393Iona Pebbles, Scotland, term used by Ramsay (1957, p. 33-35) for agate pebbles from Scotland. See also Iona, Argyllshire, above.
1394Iowa, sub-variety of Lake Superior Agate, adv., Gem Exchange, The Mineralogist, v. 7, no. 2, p. 59.
1395Iowa Agate, Iowa, term used to describe a variety of Lake Superior agates that were large and had fine bands, adv., Gem Exchange, Hobbies, v. 44, no. 6, p. 114; adv., Allan Branham, The Mineralogist, v. 14, no. 9, p. 469. Zeitner (1964, p. 345) suggested this was an agatized coral that is made up mostly of the same genus of coral composing the non-agate Petoskey Stone of Michigan.
1396Iowa Silicified Coral, Iowa, mostly silicified corals of Devonian? Age, illustrated in color in Zeitner (1978, p. 2100-2110).
1397Iris Agate, any agate that shows a diffraction grating effect by breaking light up into its component colors when viewed in thin slices held to usually incandescent light. Originally thought to be restricted to only colorless agates, but can be modified in colored agates. See Jones, Sinkankas, Pabian & Zarins, 1994, etc.
1398Ironside Thundereggs, Oregon? see Zeitner (1979, p. 1260-1272).
1399Ironstone opal, Australia. Opal in limonite concretions? adv., International Gem Corporation, The Mineralogist, v. 25, no. 4, p. 159
1400Island Agate (=Lake Superior Agate?), no further details, adv., Keweenaw Agate Shop, The Mineralogist, v. 14, no. 6, p. 333.
1401Isle of Mull, Scotland, Argyll, Scotland, an historic site that has yielded mostly blue-gray agates from basalts of Tertiary Age (Macpherson, 1989, p. 19, 49, figs. 108, 109). Rodgers (1975, p. 85) listed sites at Scobul and Scour and Macpherson (1989) called the site Ross of Mull, which is a westward extending peninsula along the south shore of the island. Fallick et al (1985, p. 622-624) studied oxygen isotope ratios in some of these agates and Field (1989, p. 16) illustrated and excellent example from here.
1402Isle Royale Agate (=Lake Superior Agate), for Isle Royale, Michigan. Now Isle Royale National Park. adv., Keweenaw Agate Shop, The Mineralogist, v. 13, no. 7, p. 241.
1403Isle Royale Pebbles (=Lake Superior Agate), name appears in adv., The Gem Exchange, Hobbies, v. 43, no. 1, p. 110.
1404Isopachous laminae, term used by Gray, Steinman, and Anderson (1978, p. 45) for bands in agates from Connecticut.
1405Itapetinga Agate, for Itapetinga, Sao Paolo, Brazil (Mattos, 1974, p. 5).

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.