I am pleased to announce the release of Volume V in my agate series. It is titled: “A Field Guide to the Agates, Jaspers, and Opals” with the subtitle “Specimen and Inclusion Identification Using Infrared Spectroscopy.” It is 327 pages, printed on 8.5 x 11 paper, full color, spiral bound. It is priced at $215.
In Volume VI, I set the groundwork showing the use of infrared spectroscopy to study silica mineral species. With the power of infrared to study opaline forms of silica that other techniques cannot resolve, a number of new species in the agates, jaspers, and opals were described. Due to limitations of earlier infrared technology, all of the species could not be found. Why so? If you bash your specimen into a powder to scan in infrared, you get one graph and call it silica X. You assign a name what X is. If you use reflectance infrared with the most modern reflectance detector cell made, you can study whole specimens, roam around and find (egad) your specimens have many kinds of silica, particularly many kinds of opal in them. So scientists in the old school report opal-A makes opal-C makes opal-CT, but I get to see specimens never with opal-A, but full of opal-C and CT and T and chlorite and bentonite pretending to look like opal, and all sorts of other interesting things. Opal mixed with quartz (oh no, say it isn’t so), and cristobalite intruding with bentonite into agates, particularly on the outer shells. The old school simpleton world suddenly lights up, and becomes quite complex. Now it becomes much harder to infer opal-C makes CT when they are all together in the same specimen. How was that supposed to work? Right, it doesn’t, and a new model view had to be developed.
Comparisons to reference scientific literature to describe these, were provided in Volume IV. This set the scientific background for the study of agate structures. In addition, I have superior melanophologite and tridymite graphs, of a quality and detail unlike any that have come before. Volume IV provided a more detail explanation of infrared spectral graphs, proving that infrared shows complex elemental organizations such as SiO2 and SiO4 and others, as well as reporting crystal structure. So the data now shows much more detail. Quartz, reported as SiO2 with an SiO4 structure now shows up as a combination of SiO2 and SiO4, for example. This goes for quartz crystals, milky quartz, and agates.
Now I can show you if a specimen has silica, in what form, if it is crystalline or amorphous or granular, and if it is blended from several forms. The graphs become quite straightforward, but it takes a huge inventory of samples to compare, something apparently not done before. The reference tables cover hundreds of specimens of the West and the world that I studied, not one or perhaps two that then make up a standard research paper. The text covers 4 new spectral bands of silica discovered and identified in infrared. Infrared provides a combination of mineral composition and structure. In the past, infrared was called unreliable. I call this “Smart machine met a bunch of dumb scientists.” That is too bad that such a perception persisted for so long and to this day. Perhaps I can help turn that around.
From that study and expanded classification of silica species, and armed with a superior understanding of how infrared reports mineral structures, I decided to put out a book covering all the major silica sites of the Western US, all of the major silica specimens introduced from foreign mine sources around the world making their way into local trade shows, and also to provide an infrared reference basis to show what is and is not an agate, jasper, and opal. These are only ambiguous terms to lazy scientists, but are specific terms shown in this text.
Armed with that, we can now identify real from fake agate specimens, in particular the carbonates being commonly sold as agates and jaspers at this time. As agate prices increase there is a disturbing trend for more imports to introduce carbonates such as complex travertines as agates and jaspers. Many lavas and silicates are also being introduced as agates and jaspers. Did you know spiderman jasper is not jasper? This Oregon material has red veining in black matrix. It is a complex volcanic rock composed of quartz and two silicates. Part of this problem is due to the confusion over the definitions, lack of study, and errors in identification of the agates, jaspers, and opals. The other reason is just fraud. It elevates the value of merchandise for sale when, say, a rhyolite is sold as a jasper. Rhyolite is common and can be mined by the ton, but jasper cannot, so jasper has a higher retail value. Starburst jasper is no jasper, it is lava. Would you think that would affect the price? For those vendors selling this material that do not care, you probably do.
Part of the success of any mineral industry is the support of identification of material properly. The Bumblebee Jasper from Indonesia has no silica. It is a travertine with sulfur. The Kabamba jasper is albite feldspar from Madagascar. The Mexican Lace is all travertine, although the name with “Lace” in it appears to delude the buyer into thinking it has something to do with Mexican Lace, a true agate. The use of the terms agate, jasper, and opal are used to cheat people that have the right to know what they are really buying.
I would estimate a third of what is being sold is misidentified at rock trade shows and online retail sites, and another third is just fraud. The purpose of this book it to show sample specimens of all the popular agate, jasper, and opal specimens being sold today, and show their spectral infrared graph for each, showing what they clearly are. I did this with a Magna 560 spectrometer, a high-end, research grade infrared system. I have two reflectance detector cells for it, and parts to upgrade to far infrared have just shipped out to me for future research.
Beyond just that, the proper identification of major worldwide specimens is provided in Volume V. Also provided are examples of the calc-silicas, the agates that are combined carbonate and silica. Agates are full of carbonates, and this text help you start to recognize them visually. Once you see the photos and their ID, you can learn their appearance to identify them visually in the future. The agates are also full of clays, and the text shows a half dozen major clay species that contribute to the complexity of agate structures.
A number of volcanic rocks are consistently reported as jaspers, so the full infrared on how I identify basalt, rhyolite, andesite, the glasses such as obsidian, and how to distinguish them from the true jaspers. For example, if you look at a black jasper from Gem Hill, it looks like a basanite. A basanite is considered a low-grade obsidian. In infrared, basanite is full of feldspar, reducing the reflectance we identify with high-quality obsidian glass. Then I looked at the Gem Hill material. It is a true black jasper, and clearly so. The is no ambiguity in its identification, as the graphs for obsidian and for basanite are clearly different. This, and many other examples of common local material are presented in Volume V.
Then, for the enjoyment of the science, I show, for example, a full graph of melanophlogite, a unique silica species. Did you know there is a site on the San Andreas that is massive quartz with that exact spectral signature? A signature so unique, I have never seen it in any published spectral database or literature source? It is an amazing world indeed, and worthwhile to expand upon what we know.
All of the specimens with mysterious structures that have fascinated and confused collectors here in the West for the past 75 years have been scanned, analyzed, and are reported in Volume V, including many of the structures in the Western geodes. I spend several pages going through the elusive Trent Oregon agate with its orange needles, to identify it. Does it have stibnite? No chance. Does it have cinnabar, realgar, and orpiment? No chance. I have reference specimens to compare for all that, and the lack of a match is clear. So what does it have? The agates are full of clays, calcite, and sometimes zeolites. Rarely they have some sulfides, that commonly intrude late. When you realize that, then the answer drops out, but this time the analysis is based on a scientific study, instead of a lot of rambling guessing.
You can see the book table of contents showing the specimens studied at donaldkasper.com, the only place you can buy it.