Yes, but if you have something the other tribe wants to trade for, and you demand payment in currency, the other tribe will quickly catch on to the meaning of currency, or go without the resources/items they want from you.
The problem with currency in Xsyon is that you get it from scavenging, which is a theoretically unlimited supply. That leads to massive inflation, because the pool of currency grows as fast as people are prepared to scavenge it...
The reason currency has value in RL is because to begin with it was guaranteed by state banks (and still is). So if you are given a £10 note the value of that money is guaranteed by law. On top of that the law requires that it be accepted as payment for goods and services. I suppose for a currency of any kind to take off in Xsyon we would need inidivdual tribes to guarantee the value of whatever they use, be it dollar bills or bones, will be upheld for all transactions within their "state".
In the past gold has been used because it has historically had a steady and comparable value to other items. And so something suitably rare but not TOO rare would be required for a more primitive system.
Inflation - thye tribe would have to have the ability to control the amount of "currency" thats circulating within the tribe. This can only really be done with a unique crafted tribe item or stamped coin for example.