| Original Message: Re: Some Amber Info |
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Hi Chris, The page on amber is pretty good, but I would have to disagree with some statements. The "cherry red" Baltic amber that is commercially available normally is not merely a product of heat treatment. It is also dyed (as well as heated). Whether treated amber is considered to be "gem quality" (as though it makes no difference) is a matter of opinion (!). Some people would say that only high quality NATURAL amber is truly "gem quality." Unfortunately, many treatments are so skillful or benign, there is almost no way to say, for sure, whether a piece of amber is "natural" or not. In Germany, it is illegal to sell treated amber as "natural amber." It must be characterized as "genuine amber." But the issue of its being "gem quality" is a matter of opinion. On the issue of sun-spangles, what is written is a bit misleading. These are indeed caused via heat-treatments. However, the way it happens, tiny drops of water (or gas) expand during heating, and the internal pressure (from expansion) causes a tiny fracture to happen. The typical shape of these fractures is flattened and oval or circular. From the time this process was devised and used, from the 1800s, it was a secret, and manufacturers apparently encouraged the speculations that these were "inclusions," and may have been "seeds," "eggs." "fish scales," "one-celled life," etcetera. In point of fact, sun-spangles were originally an unintended by-product of clarifying (cloudy) amber. They were not intentional. The workers tried very hard to avoid these artifacts. However, eventually, they found that people LIKED the effect, and the secret—that they were artificial, from clarifying processes—was kept from the public (who were only too enthusiastic to speculate what these "inclusions" might be). It is hilarious that the author writes, "The amber must then be cooled very slowly or it could fracture easily." The treatment, itself, is a fracturing treatment. The author is essentially talking about the clarification in hot oil of cloudy amber. This process demands that the amber be heated slowly and then cooled slowly (the books say for 24 hours to get hot, and 24 hours to cool down)—to avoid the occurrence of sun-spangles (!). If sun-spangles are desired, the work can be rushed—because this is what CAUSES the effect. Eventually, sun-spangles became so popular that rather than make them as a by-product of clarifying, workers actually took clear amber and (dry) heat-treated it to CAUSE fractures. So, when the author writes, "The small circular fissures in the amber are encapsulated water droplets that flatten to disk-like shapes when the amber is boiled," this is not really accurate. The amber is not boiled (because it is no longer opaque amber being clarified). The clear amber is immersed in sand, and heated. The water drops do not "flatten to disk-like shapes." The water explodes and causes a tiny flattened fracture. Finally, the statement that "Milky, creamy, and lemon amber are examples of natural colors which have not been heated—obviously, you don't see the 'sun spangles,'" is a bit disingenuous. These varieties of amber are not clarified (which is what the author has been talking about)—so, of course, they are not 'boiled in oil." However, the lack of sun-spangles is NOT proof of their naturalness. As I mentioned above, sun-spangles were originally an unwanted by-product of heat treating. If the work were conducted carefully, the spangles did not develop (particularly in amber that did not have drops of water that cause fractures when heated). Consequently, we can assume that sun-spangles are typically an indication that the amber has been heat-treated. But the opposite is not necessarily true. Just because there are no spangles, it does not follow that the amber has not been heat-treated. It's possible it WAS heat-treated, but that the result was very good. I hope this "clarifies" some issues related to amber treatments. Jamey All rights reserved by Bead Collector Network and its users |
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