Why Do I See Coral Jewelry Elsewhere For Much Less?

Very good question.  The answer is both simple, and not-so-simple.  The simple answer is that "Genuine" fine Coral, like fine Jadeite, is both rare and expensive.  Vintage pieces in particular are sought by collectors and jewelry connoisseurs and, accordingly, command very high prices in a very competitive marketplace.
The not-so-simple answer is that the jewelry marketplace is literally flooded with counterfeit Coral being marketed as genuine, gemstone quality, Coral.  There are any number of materials that are used in the fabrication of counterfeit coral from plastics, to glass, colored ceramics, to actual Coral fragments that have been ground to powder, dyed, mixed with resin, cast and polished, and sold as natural, untreated, Coral.  In the latter case of resin-based powered Coral, the seller can legitimately advertise the item as "Coral" - albeit not as "Natural and Untreated Coral."  
It is very, very difficult for the average buyer to discern the real from the counterfeit.  You cannot rely on the setting used for the Coral, as Silver, Vermeil, and Gold are used as settings to create the perception of the setting holding a genuine piece of quality Coral.
Below is an example of a bracelet found for sale in a local Antiques & Collectibles Shop. It was presented as a genuine Vintage Coral Bracelet with an asking price of $250.00.  It is absolutely counterfeit.  The owner, whom we know, was not intentionally selling counterfeit goods, but not being experienced in Coral, genuinely believed it was good Coral.  He has since removed it from sale.  Were it a genuine, gemstone grade, Vintage Coral Bracelet with this detail, you could expect a fair market value of $2000.00 or more.   Also below are a pendant and pin in gem-quality Coral and their realized auction prices.
Just as you would be suspicious of anyone advertising 1-Carat Diamonds for $100 you should equally be suspicious of Coral being sold at low prices.  Your best defense is to familiarize yourself with Coral-as-a-Gemstone, and do some basic research before you buy.  Visit reputable sites: Sotheby's, Christie's, Cartier, Van Cleef and Arpels, even 1stDibs, and note their prices for custom, high-quality, Coral.  Finally, buy from trusted dealers and ONLY those who will offer you a full money-back guarantee on your purchase if found to be anything other than natural, untreated, Coral.
We offer that guarantee on all of our items.  Simply, "It is what we say it is, or your money back."

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