How Low (On Silver Content Below 70%) Can You Go?

For Spence's 0.208 (21%) - presumably 2 deniers 12 grains? - I have this French 30 deniers (mousquetaire), dated 1710, Metz mint (mintmark AA), Numista 22499; apparently KM# 378.1 but Numista doesn't mention this.

This type is listed in the Red Book, as a colonial coin! Apparently it was first identified as colonial in the late 19th century. A more detailed backstory in this Stack's Bowers listing.
...AFAIK later research had found that, while some other variants of this type did circulate in the French colonies in North America, the 1710-AA specifically probably didn't.

The Lithuanian denar is indeed listed in Gumowski at same (0.219) as the 2 denars. I can't find the Gdansk denar of Sigismund II in Gumowski, but under Sigismund I (1539-1548) it was lower, 0.094. Will look into it.



Neat that we are finding coins spanning 7 centuries for this thread! I will add to the comprehensive list next time it's updated.

I have posted this coin earlier on the CCF some time ago, namely:
Turkey/Ottoman Empire 1223/23 (1830) 5 Kurus of Mahmud II, N#79638, and according to Numista has a percentage of silver of 22%...

So far, this would be the most recent coin on our list in the 20's% range...

A little more than that - the earliest coin posted so far is from the reign of Louis IX of France (d. 1270), so if we're counting centuries by number we have 9 of them represented.

For the 10-19% range I have a late 14th century coin at 11%, which is AFAICT the oldest coin in my collection with a known official fineness.

Found some ways to try to sort these out a bit.

1807 6 Kreuzer - Baden, 37.5% silver




1850 3 Kreuzer - Bavaria, 33.3% silver





1866 3 Kreuzer - Frankfurt, 33.3% silver




1855 Sechsling - Hamburg, 25.0% silver





1866 Groschen - Hannover, 22.0% silver




1835 Schilling - Mecklenburg-Schwerin, 31.2% silver





1861-A 1/48 Thaler - Mecklenburg-Schwerin, 20.8% silver





1834 6 Kreuzer - Nassau, 37.5% silver





1767-F 1/12 Thaler - Prussia, 43.7% silver





1834-K 6 Kreuzer - Sachsen-Meiningen, 34.7% silver





1840-A 1/2 Groschen and Groschen - Saxe-Weimar-Eisenbach, 22.2% silver each






1694-EPH Saxony (Albertine) - 1/12 Thaler, 48.6% silver





1812-C - Westphalia (occupied) - 10 centimes, 20.0% silver





1839 and 1840 - Wurttemberg - 3 Kreuzer and 6 Kreuzer, 33.3% silver each

Indeed! Though a bit like drinking from a firehose .

Two new compositions added to 20-29% (and the others will be updated into the comprehensive list). We are now up to 8 compositions accounted for!

29% Poland 6 groszy KM#155 (tdziemia)
28% County of Flanders 1 groot N#98102 (tdziemia)
25% East Africa 1 shilling KM#28 (oriole)
.......German States/Hamburg sechsling KM#585 (paralyse)
24% France/Brittany liard 1492-1498 N#178499 (erafjel)
23% Poland Elbing schilling N#107714 (tdziemia)
22% German States/Hanover 1 groschen KM#236 (spence, paralyse)
........German States/Saxe-Weimar-Eisenach 1/2 & 1 gr KM#198, 199 (paralyse)
........Lithuania 1 denar N# 46192, 175323 (january1may)
........Lithuania 2 denars N#36694, (tdziemia)
........Poland 1 denar #175270 (january1may)
........Turkey/Ottoman 5 kurus KM#591 (mrwhatisit)
21% France 30 deniers KM#378.1 (january1may)
........French Guiana 2 sous KM#1 (Hondo Boguss)
........German States/Mecklenberg-Schwerin 1/48thaler KM#311 (paralyse)
20% German States/Westphalia 10 centimes KM#96 (paralyse)

(Edit: List updated January 2, 4 p.m.)

I need modern photos for many of them, but time has not allowed.

Super! Will add to the comprehensive list next time it updates. I think that puts us at 33 out of 40 possible compositions between 69 and 30%.


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Not too bad ... I mean the eagle still has all its feathers .