"For example, a 'double tarn' is twice the weight of a 'tarn'. It seems
there are usually eight tarsk bits in a copper tarsk, and that these are
the result of cutting a circular coin in half, and then the halves in half,
and then each of these halves in half. An analogy would be cutting the round
, flat Gorean loaves of Sa-Tarna bread into eight pieces. There are
approximately something like one hundred copper tarsks in a silver tarsk in
many cities. Similarly, something like ten silver tarsks would apparently be
equivalent, depending on weights, etc., to one gold piece, say, a single
'tarn'. Accordingly on this approach, the equivalencies, very approximately
and probably only for certain cities, would be eight tarsk bits to the
copper tarsk, one hundred copper tarsks to a silver tarsk, and ten silver
tarsks to a gold piece, a single tarn. On this approach, there would be,
literally, 8,000 tarsk bits in a single gold piece."
Magicians of Gor, footnotes, page 469
So, using this formula: "Without speaking, the man took twenty pieces of gold, tarn disks of Ar,
of double weight, and gave them to Kuurus..." Now, to give some idea of what that means in terms of prices of things...
"Five pieces of gold, in its way, incidentally, is also a fortune on Gor.
On could live, for example, in many cities, although not in contemporary Ar,
with its press on housing and shortages of food, for years on such
resources." "...In many paga taverns, one may have paga and food, and a girl for the
alcove, if one wants for a single copper tarsk. Dancers, to be sure,
sometimes cost two." "A golden tarn disk was a small fortune. It would buy one of the great
birds themselves, or as many as five slave girls."
8 copper tarks bits = 1 copper tarsk
100 copper tarsks = 1 silver tarsk
10 silver tarsks = 1 gold tarn
Assassin of Gor, page 4
Magicians of Gor, pages 468-469
Renegades of Gor, pages 51-52
Tarnsman of Gor, page 191