Tarsk Bit

A copper coin worth from 1/10 to 1/4 of a copper tarsk, depending on the city which mints the coin.

To be sure, much seems to depend on the city and the particular weight involved. 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 haves in half. An analogy would be the practice of cutting the round flat Gorean loaves of sa-tarna bread into eight pieces. There are apparently something like 100 copper tarsks in a silver tarsk in many cities. Similarly, something like ten silver tarsks would apparently be equivalent, depending on weight, 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 one copper tarsk; one hundred copper tarsks to a silver tarsk; ten silver tarsk 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, page 469

 
Copper Tarsk

Worth between 4 and 10 tarsk bits depending on location. 100 tarsk bits make up a silver tarsk, and equalling 10 tarsk bits.
tarsk, silver: worth 40 copper tarn disks or 100 copper tarsks. 10 silver tarsks make a gold tarn.

 
Tarn Disk, Copper

1/40 of a silver tarsk.

Nela was an expensive girl, though there were pools where the girls cost as much as a silver tarn disk. The tarsk is a silver coin, worth fourty copper tarn disks.
Assassin of Gor, page 160

Tarn Disk, Gold

 Worth 10 silver tarsks, also comes in double weight. With the exception of the double tarn, a gold tarn disk is the highest value coin on Gor.

Although it is not my policy to include Cabot's marginal notes, jottings, etc., which are often informal, and apparently written at different times, in the text of his accounts, I think it would not be amiss to hypothesize certain approximate equivalencies here. To be sure, much seems to depend on the city and the partiular weighs involved. 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 the practice of cutting the round, flat Gorean loaves of sa-tarna bread into eight pieces. There are apparently something like one hundred copper tarks in a silver tarsk in many cities. Similarly, something like ten silver tarks would apparently be equivalent, depending on weights, etc., to old gold piece, say, a single "tarn." Accordingly, on certain cities, would be eight tarsk bits to a copper tarks; one hundred copper tarks to a silver tarsk; and ten silver tarks to a gold piece, a single tarn. On this approach there would be, literally, 8,000 tark bits in a single gold piece.

Magicians of Gor --page 468

Tarn Disk, Silver

 Worth more than a silver tarsk, they don't state an exact amount. 

"The odds are usually one to forty, one copper tarn disk against a forty-piece."
Assassin of gor, Pg. 29 

"The tarsk is a silver coin worth forty copper tarn disks"
Assassin of gor, Pg. 160 

"One of the guardsmen opened her mouth, not gently, and retrieved the coin, a rather large one, a tarsk bit. Ten such coins make a copper tarsk. A hundred copper tarsks make a silver tarsk."
Explorers of gor, Pg. 54 

"'If Ar were to produce debased coins,' I said, 'her trade were be reduced, if not ruined.'"
Marauders of gor, Pg. 76