The silver standard thing is a bit setting dependent but I think Alex explains it best here. That's for fantasy England and medieval Europe. In al-Qadim, a gp also match well up to a historical gold dinar in both market value and weight, and an sp to a silver dirham. I.e. same standard, they just were more likely to actually have 1 GP than to have 10 SP.
1e and B/X has 10 coins weigh one pound (which is why Delta and LotFP want to use the silver standard),
5e has 50 coins weigh one pound,
and ACKS has 100 coins weigh one pound. 5e's econ and prices overall matches well up to ACKS (with one big difference: wealth-by-level is around 5 times higher in ACKS).
If you want to continue this in a new thread, I'll be there (these "What did you play this week" threads are pretty singular in purpose but I was really happy to be able to read some of your house rules).
I don't buy Alex's explanation because of inuition about the actual value of gold and the relative cost of living and wages in Byzantium, which the default ACKs setting is based on. I have a vague memory of an elite cavalryman being paid 12 gold coins while meager living conditions in ACKS are calculated at 3gp per month.
The unit of weight in ACKS is stone, which in the game is either 6 items, an unwieldy thing like a bow or a spear or about 10 lbs or 4.54 kg. The pure gold coin of Byzantium and late Rome was called the Solidus and weighed 4.5 grams which is almost exactly 1,000 coins to the ACKS-stone. Better yet the coin wasn't debased till later in the 11th century letting us compare it to other gold coins of equal weight.http://www.roiw.org/2006/2006-22.pdf
This paper compares Byzantine wages with the cost of military and monastic rations. Monastic rations are assumed to be the subsistence minimum as they are close to the minimum caloric intake for an adult male (military rations cost about twice as much as they include more meat, oil and wine).Historical
Unskilled work: 12 gold coins/year
Military ration: 6 gold coins/year
Subsistence minimum: 3.5 gold coins/yearACKS
Unskilled work: 36 gp/year
Wretched living conditions: 12 gp/year (I take this to be subsistence minimum)
Meager living conditions: 36-144gp/year (living standard of most laborers and soldiers)
If we just take the subsistence minumum we can see that the ACKS gp is worth 0.29 Solidus, or to put is the other way, 1 Soliudus ~ 3.4 gp. Comparing the compensation for unskilled work gives us the ratio 1 Soliudus = 3 gp. In conclusion
: In ACKS the value of gold is 29-33% of the historical value. In my campaign where 1 gold coin = 10 gp the value of historical gold is 30-34% of the value in my campaign. So under these conditions (provided that the 1:10 gold:silver ratio is true, it was unpopular for coins in Byzantium because of the unstable price relative to gold) the gold standard is exactly as wrong as the silver standard.
My main gripe with the default ACKS weight system is how a piece of jewelry like a golden crown can worth thousands of gp while the gold weight is ~166gp, I want the value of a piece of jewelry to be close to the scrap metal value unless it's made with extraordinary craftsmanship.
Anyway, if you see a flaw in my reasoning here feel free to point it out.