Wow! It's taken me a while to weigh in on this. That arrangement of Pau pearls just stuns me! What a beautiful suite. Words cannot do justice. This is carrying one-of-kind to its' top end. I'm sure there must be nothing else like it in the world. Simply amazing. Thank you for showing this to us.
It's been my intention to take part in this thread all along but I have nothing on a par with that grand spectrum to show so I won't even try. Rather, I will explore examples and issues on more of an individual basis. As well, I take part in PG more as a way to educate myself on many of it's myriad subjects rather than as someone with any related expertise (Other than goldsmithing.) When I weigh in on any subject I do so as a student seeking to learn and that is what intrigues me about the subject of this thread.
I think that there are a number of aspects to abalone color that we might look at. It seems to me that the color in these mulloscs is caused and influenced by several factors. Some of these are iridescence, the base color of the shell material, conchiolin, layer thickness, thickness of cumulative layers, shell transparency. . . I'm sure that there are other influences as well, such as weathering, sun bleaching and who knows what all.
I spent a few hours reading, rereading and checking out references in the threads of the Pearl Guide trying to understand the concept of "orient" over the last couple of days. After looking at shells over and over again and thinking about it I've come to the tentative conclusion that, for at least a couple of reasons, it doesn't apply to abalones, at least in most of them. I state this as an example of something we could explore and that I'd like to hear others opinions on.
I also find that it is quite difficult to discern the base color of the shell material--these things tend to be so wildly iridescent! I'm going to try to cut some very thin sections of the shell and look through them with transmitted light rather than refracted or reflected.
Since New Zealand Natural Pearl has us thinking in terms of color range, I'll post some pictures that I have taken that show some interesting variations of color in west coast USA abalones. The first two are from the edge of the muscle scar area in the center of the shell. The blisters themselves show the layered effect that the shell there has and these are good examples of the just how colorful they can be. It is also, I'm afraid, an example of how the time of day may affect the colors. These were shot very late in the day, near sunset and seem to by missing most of the yellows that I see in them more to the middle of the day. The third one is not at all common in that it shows somewhat more than a 50% preponderance of a gold color. This seems to be a result of a thin layer of conchiolin that was starting to be deposited at the time of it's demise. I have just a few mabe's that show this in varying degrees, this being the best example. This conciolin seems to be as hard and durable in the pink and red abalones as the nacre. The last picture is of a mabe' from a black abalone showing the lighter tone and the delicate shading to the iridescence in the shell of these creatures.
Marc
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