This practice survived into the nineteenth century in the sultanates of Perak and Selangor. The currency systems of the sultanates also used more conventional forms of money, such as gold and tin coins and imported Spanish (later Mexican) silver dollars.
It has been suggested that these tin animals were originally intended as talismans, weights or even toys, but it is clear that they were also accepted as currency. In the Kinta Valley of Perak, in the mid-nineteenth century, one gambar ayam (cast tin cockerel) was valued at 10 pitis (tin coins) or 100 duit ayam (copper tokens bearing the image of a fighting cock that were issued privately by certain Singapore merchants).
Reference: The British Museum