Hi Christian, thanks for your reply, but isnt it the case with these thalers that all the thalers after 1780 bear that date? And that the difference can be seen in small details?
Basically yes; the Maria Theresia Thalers made after, say, 1850 look pretty much the same, so with a 20th century MTT one cannot tell when it was made. But there are many variants among the earlier ones. Problem with your "rattle thaler" is that some details are not visible, due to wear and because the soldering "hides" them. If you look at the site that willieboyd2 mentioned and go to the lists of variants http://www.theresia.name/en/svariants.html , you may find some more help. Or maybe somebody else here can provide more info? Christian