How many coins can you put in a weapon in "Dark Cloud 2"?

According to Cheat Codes, there is no limit to the number of coins that can be put on a weapon in “Dark Cloud 2.” In total, there are 10 unique synthesizing coins.

Each coin in Dark Cloud 2 has a special ability. Adding a coin to a selected weapon gives a certain special ability to that weapon. Most of the coins that players obtain in the game are found in treasure chests. Locked treasure chests have a particularly high chance of containing a coin. Later in the game, players are able to buy these coins. The in-game price of the coins ranges from 1,500 for a dark coin to 12,000 for an experience coin.