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Hi there, I am looking for accurate replicas of actual dinosaur fossils: claws, teeth, skulls, skeletons, etc. I have seen several different resin replicas floating around eBay and Amazon, etc. but I am not looking for toys or other enhanced replicas or cheap models. I am looking for actual casts of real specimens, something worthy of a museum (maybe not museum price though?). I am especially interested in claws and skulls, both for reference material and display. Something durable too, so no ceramic, glass, etc. Does anyone know of a reputable site for this? Also, if you have any cool replicas, I would love to see them. Post pictures of them here! @Troodon
I have been doing some recent work with Columbian Amber/Copal and thought I would throw this out for a general discussion. It is fun, if nothing else Most of my life I have believed that there is no difference between Copal and Amber. I know chemically there is no difference between the two. Amber/Copal from the same plant from different time periods, even millions of years apart are identical. Fossil resin's molecular make-up is mostly carbon and hydrogen atoms that form hexagonal rings. Molecular bonding between the rings increases over time (called polymerization, as in modern epoxy resins), and the tacky resin becomes hard. For all practical purposes, the hardened resin is a "plastic". Exactly when the resin becomes amber/copal, or a fossil, is not definable by any scientific criteria. I would like to see if others have the same thoughts. I am also attaching a picture of the best piece in my collection. "Best" meaning my favorite. This is one of my favorite articles. The following is by Dr. Robert E. Woodruff Emeritus Taxonomist, Florida State Collection of Arthropods Resins are produced by many trees and other plants; Frankincense of the Bible is one of these. Peach and Cherry trees produce resins that children often use as chewing gum. No botanist or paleontologist knows when resins were first produced, but we know it was probably more than 100 million years ago. They are produced to heal wounds, just as our blood coagulates to seal injuries. There is no doubt that these resins have been produced continuously since they first occured. Because they are affected little by the elements, resins are similar to their original form. Only a few volatile oils are eliminated by time and burial (e.g., in marine sediments that are 3000 ft. elevation now). We use Canadian Balsam as the most permanent sealant for cover slips on microscope slides. Unfortunately, no one can presently date these resins by any definitive tests. Because they have been continuously produced, there are no drastic changes from one geological period to another. We can infer age, if we know the age of a sedimentary deposit in which they are found (this would be a minimum, because older material could have been redeposited). There are those (including several scientists) that insist that the word amber must be reserved for certain age resins. With such a continuous resin production, and no clear dating, it could all be called amber. It is a semantic argument, & those who sell Baltic, Dominican, & Mexican "amber" do not want to use the term for any that might be more recent. Obviously a commercial bias is present. They prefer to use the term "copal". Strictly speaking, the Aztec word "copal" is used for all resins! They do not distinguish the Miocene deposits from southern Mexico from the recent resin collected for incense today. Therefore it should not be redefined to fit some new arbitrary definition based on age. It is considered lower class only because of these commercial interests. We have Cretaceous amber (at least 65 million years old) and much Oligocene & Miocene amber, as well as Pliocene (Africa), and many others. We have no dates or specific geological information on Colombian amber. Because of it's color and hardness, we believe it may be Pliocene or Pleistocene (as is some of the Dominican amber from Cotui). Studies underway may clarify the deposits, but evidence suggests that there may be varying geological formations & ages. Mankind (depending on the anthropologist's definition thereof) has been on earth only 3-5 million years. Certainly the Olduvai specimens are fossils (both men & animals) and extremely valuable for study of human evolution. If we assume the Colombian amber is this recent, it still has extremely important value for those studying the fossils. Studies of biodiversity, biogeography, ecology, and evolution, all benefit from the scientific description of these amber fossils. Age is relative, the old man said, but old is not necessarily better. To call the Colombian material anything other than amber is a misnomer! Logically, we should just call everything "resin", with qualifying adjectives of origin or geological formation. I doubt that this would be acceptable to most "amber" dealers!