I've heard some ways. Looking at it under a microscope to see if it has any brush marks. As I previously stated I'm not a professional so I have no idea how to test it.
Sean welcome to the fourm. What you are suggesting has already been done. Basically a PCGS grader looked at that coin and determined the toning to be natural, along with grading the coin an MS 66. You don't get any more professional in numismatics than PCGS. And you can bet if you crack out a coin from the holder there won't be any returning it. I'd suguest before spending money on coin, that you hang out here, ask questions like you are doing, and if your interested in Kennedy half dollars pick up the Red Book on them. You'll fund your money will go much further.
In a situation such as this, I know of no "professionals" who would be willing to crack out a perfectly legitimate coin, for the supposed purpose of verifying toning or authenticity, when they can easily see with their own two eyes, especially if they knew you were willing to try to saddle the seller with leftovers if you didn't like the result.
I don't really know why I like coins so much. Maybe because there so different and there's so many of them. It's fascinating to see the designs of foreign coins. You can learn a lot about a country by how they design there money. I like the Kennedy half dollars because of its simplistic design on one side and very intricate design on the other. The vibrant toning of the coin is a true work of art.
Well the good news is that you've come to the right place, keep looking at coins and asking questions. You may have to put up with some orneriness from some of the members here, but hopefully it won't deter you form perusing the hobbby. Here is a pretty standard price guide folks use for assessing a coins price. http://www.numismedia.com/fmv/prices/kenhlv/pricesgd.shtml The online price guides always seem to be a bit inflated when compared to the paper guides like Coin World and the Blue Book. Red book's prices are also inflated a bit. Pcgs has a price guide as well, put as someone mentioned already it's a bit high as well. If you're going to buy on ebay, the best thing to do is run a bunch of searches on completed sold autions. You can do that from the advanced options to the right of the search. This will show you what a specific coin is selling for currently. Hope this help's
PCGS has a sniffer machine that supposedly detects artificial toning, see link below. There's no way possible that coin is worth $250. Sure, maybe $50 to $75 but I don't think it should sell for a penny more. That's just my opinion btw, here's one of my toners. As far as the Kennedy goes, it's a very nice coin but the seller is trying to put the screws to some haphazard buyer. Pass. http://www.coinweek.com/education/c...e-pcgs-coin-sniffer-to-detect-doctored-coins/
Are you serious? 1964D Kennedy in PCGS plastic MS66 should run you between $90 - $135 (a die variety will be extra) toning has no value to me.
Well that's your opinion. I love toning and think it looks nice on this coin. But if you don't that's fine.
If most online guides are inflated compared to trends, things must have changed more than I expected. As for the bluebook, its worthless for anything beyond he widgets of widgets, so save your money, or just burn it; 'tis about the same thing. All this talk about the sniffer for an already certified toned coin... (Roll eyes here).
First - How would "test" it? Second - the seller describes it as "Rainbow Toning". You can see what it is, what would tell you it's "fake"?