Apparently it was not that long ago that Reader's Digest magazine ran a promotion and produced a bunch of replica coins that look like Austrian gold ducats. Most have a date of 1752. Some carry no date. You can see an extensive discussion of this coin on CoinTalk.
Genuine ducats are things of elegant beauty. In the comparison below, check the overall crisp appearance and intrinsic appeal of the genuine coin from Stacks Bowers to the mushy and lifeless appearance of the fake.
Especially in this day and age of high-tech counterfeits, is it absolutely necessary that any serious collector deal with fully reputable, nationally recognized coin dealers. A quick peek at CoinQuest's Counterfeit Collection will sober any prospective buyer of rare and valuable coins.