1613 German States Brunswick-Wolfenbuttel Thaler

German SS, US VF details, heavily cleaned and possibly ex-jewelry/mount removal. Rims damaged. File adjustment marks very light and only on the upper right reverse.

This is a most interesting coin. It was struck at least twice and more probably three times (triple-struck); it was only struck in this particular design from 1613-1615, and there are different varieties (the reverse on yours has BRUNSVIC, instead of the more common BRUNSUIC) -- if it is authentic it's a high three-figure (USD) coin even in this condition, and quite scarce.

Here is a short video where I attempt to capture the texture of the coin. For lack of a better description, it seems to be bulge toward the center of the obverse, basically a bit convex, but not in a uniform way. The reverse could be slightly concave, its hard to tell.

You can see it is "non-uniform" in the following locations:
About 11 o'clock from the crook of the elbow out to the rim. The obvious one between 3 and 5 o'clock, and another between about 8 and 9 o'clock.

@Jadey I'm no expert but have a good familiarity, so thank you.

17th c. thalers from Munich such as this one were coined on a roller press. A strip of silver was prepared to the correct thickness and then fed into two rollers with the design of the obverse and reverse engraved on them. As the machinery operated, the action of the press would force the strip between the rollers; it was then advanced to the next spot on the strip and the process repeated. Each "struck" coin on the strip was literally cut out from the strip by hand, resulting in rims that were wildly uneven in texture and often out of round. Wear to the dies, the mechanical roller assemblies, and varying thickness of the strip metal resulted in wildly uneven "strikes" with noted concavity or convexity, which sometimes confusing unknowing collectors who might think the coin was bent. The coiner(s), if the coin did not "strike" well, would simply back the strip out and "restrike" the coin, sometimes multiple times, until it was satisfactory. Once the coin was cut out, and deemed satisfactory, it was then weighed to the standard -- too heavy and it would be filed down to remove metal, too light and it went back into the melt pile to be melted down and made into a new strip. Despite the age they were made in, the finished coins had an impressively low variance in weight, to within two or even three decimal places, a precision and quality that made them greatly useful and admired in trade.

Nowadays with modern coin machinery, a misaligned die strike occurs when the dies are not perfectly parallel or the strike pressure is uneven, resulting in some areas of the coin that are weaker than others, and this is really just the 17th c. version of a misaligned die strike with multiple strikes.

Compare this to hammered coinage, where blank planchets (sometimes pre-cut and pre-adjusted) were inserted into the "anvil" or lower die and then given a heavy blow from the top "hammer" die or from a large actual hammer (by hand, or more likely by means of a winch-and-pulley system) - the planchet tended to "jump" when it was struck, resulting in similar striking oddities.

This 1643 Swedish solidus of Christina (struck in Riga, Latvia, under Swedish occupation) is a good example of what happens when the roller dies were not properly aligned -- a normal strike on one side and badly off-center on the other side. You can see part of a 2nd coin on the OC side, evidence that these coin blanks were mechanically punched out of the feed strip, and not cut out by hand.

Actually, they were, especially on the higher-fineness coins :)

As Europe's communities transitioned to market economies, standards such as the Cologne mark, the Tower pound and the Troy pound were established to set a "baseline" weight for a given amount of silver or gold. All coins were then based on whichever "unit" and fractions of that unit. With many folks unable to read, weight was more important than written denomination when it came to day-to-day business.

Let's use an example (with modern measurements) - a Bavarian Konventionsthaler of 1763, popularly known as the Madonnentaler for the depiction of the Madonna and infant Jesus on the reverse. The "standard" for this coin was set to 27.92 grams of 0.833 fine silver, the remainder composed of copper and trace elements. This weight was exactly 1/10th of a Cologne mark. In 1763, this diameter was set to 40mm, and the thickness was set to 3mm.

1 Konventionsthaler = 27.92g

1/2 Konventionsthaler = 13.95g

But then it gets tricky:

1/6 Konventionsthaler = 20 Kreuzer (1 Konventionskreuzer)...but 0.583 fine silver, instead of 0.833 -- so the weight is 6.68 grams, instead of the expected 4.65g @ 0.833!

And then it gets even more tricky:

1/12 Konventionsthaler = 10 Kreuzer...but the fineness is now dropped to 0.500, so the weight is 3.72g instead of 2.30g @ 0.833.

(This was done as a matter of convenience to prevent the minors from being super-lightweight in smaller denominations and also to "disguise" the debased fineness. Denominations below 10 Kreuzer were copper or very low fineness billon issues denominated in Pfenninge, again, to keep weight up and costs down.)

Weight was critically important - if you were a mintmaster and struck a Thaler, if it didn't weigh to standard, not only were you impacting day-to-day business, you were affecting taxes, soldiers' payments, international trade, and you did not want your particular ruler to be slighted or embarrassed by your producing underweight or adulterated coinage with their name on it.

Even in 1763, the technology was sufficient to allow accurate measurement to the standard -- you didn't have to know that a Konventionsthaler weighed exactly 27.92g, but if your ruler put 10 Konventionsthaler on the scale, they had better balance evenly against a Cologne mark.

The German processes were sufficiently precise that even today, 250+ years later, an About Uncirculated and undamaged (not clipped or holed) 1763 Madonna thaler will usually weigh within plus or minus one or two tenths of a gram from its standard of 27.9 grams!