Legend on first picture: GOTTES REICH BLEIBT EWIG - the kingdom of god remains forever. I see only disconnected letter groups on the other side not fitting with LAVF(F)ER or NVREMBERG. What can you read yourself?
This is a counter (Rechenpfennig in German). It is used on a counting table, much like the beads on an
abacus. These products were a specialty of Nuremberg and nearby Munich. Since they were struck in a variety of brass that looked a bit like gold when it was new and because the design was vaguely reminiscent of real gold coins, many rulers required that the name and "address" of the maker be in the legend. Counters were used mostly in the accounting chambers (accountancy and bookkeeping departments) of powerful members of the nobility. Since virtually all transactions involved physical money, there was a constant temptation to commit fraud or steal money*. Counters therefore often carried religious invocations against sin, crime, fraud or stealing. In this case, the eternity of god's kingdom is an implied threat that fraudsters will go to hell and remain there for a pretty long time.
Your counter is holed. The hole is quite round. In medieval times, nails were squarish, not round, so the hole was made (much) later. When you pierce a coin, you'll get small triangular spikes, pointing down that will ruin your clothes. On your counter, those spikes were filed down to what looks like a bevelled edge around the hole: the counter was ready to be in contact with clothes. The side without the edge was to be in sight. The hole is down below (at 6 o'clock), so if the counter was hung around the neck, the image was upside down. This means that it was meant to be of use to the wearer, rather than be a decoration to be seen by another person.
The counter's function was an amulet, worn on the skin. It would be taken for old (correct), valuable and magical. Its powers were believed to protect e.g. a child against diseases or a common soldier against getting wounded or killed. When the wearer was anguished, he/she would fish the amulet out of the clothes without removing it from the neck, turn it around horizontally (so that the image was now in the correct position) and kiss it, perhaps saying a little prayer.
Peter
* compare a large clothes shop: one person controls the cash register, another checks the receipt and puts the clothes in a bag. The second person keeps the first honest. If the first bribes the second, fraud is possible.