Please Can Anyone Identify This 1772 George III Coin Weight?

Found this one, which seems to be the same: https://www.abccoinsandtokens.com/C...98O.001.html

This is pretty cool. To help me learn, could you guys help to decipher the inscriptions? I'm sure that must be George III, but what about the S? D and 10:5? And on the other side, I'm not sure what that stuff is other than a date. Thx for any light you can shed on this piece.

Yes, Geo.III is George III. Then on the same side we have s d / 10:5, which should be read 10 s 5 d, that is, 10 shillings and 5 pence. The inscription on the other side reads 2 dwt 16 gr, that is, 2 pennyweights 16 grains (0.133 troy ounce or 4.15 grams). And then the year 1772.

But, a guinea had a value of 21 shillings and should weigh 5 dwt 9 gr, so shouldn't this ½ guinea coin weight show a value of 10 s 6 d and weigh 2 dwt 16½ gr? Well, a guinea was a coin whose value was determined by its gold content (or, in practice, its weight). While the nominal value was indeed 10 s 6 d, wear and tear on the sometimes 100 years old guineas still in circulation towards the end of the 18th century, meant that the actual value could be less, depending on the weight. So this is a coin weight for guineas weighing a little less than nominal, and consequently valued at a little less than nominal. In 1774, a proclamation standardized the guinea values into four tiers, which for ½ guineas yields (somewhat simplified):
2 dwt 16½ gr - 10 s 6 d
2 dwt 16 gr - 10 s 5 d
2 dwt 14 gr - 10 s 3 d
2 dwt 13 gr - 10 s 0 d

The tiers were also tied to year of minting, so the highest tier was for "new" coins, the second highest for coins minted from 1772 and on, the third for 1760-72 and the fourth for older coins (this was perhaps not fully thought out ...! ). So the year 1772 on the weight is not the year the weight was made, it refers to its usage for coins minted from 1772 and on. (On other coin weights one can can see inscriptions like "Coined since 1772" or "Coined before 1772.")

Ok yes exactly. Thanks to both @pnw and @era for helping decipher the inscriptions. Definitely helps put this in context.