Later in the period, the northern coasts of Java and Bali became the main center of an affluent export trade in local agricultural products and manufacture, as well as spices e.g. sandalwood from eastern Indonesia.
[1] Most gold coins of 9th and early 10th century Java are stamped with the character ta in nagari script on one side, an abbreviation of tahil.
The obverse of the sandalwood flower coins are stamped with the nagari character ma (abbreviation of masa).
By the mid-14th century, there were so many pisis in circulation, that the Javanese court recognized them as official currency for tax purposes.
Similar sandalwood flower coins like those in Java were discovered in Sumatra, but more of these were made of gold, electrum, and silver alloys.
Several 11th-century sites in Sumatra including Barus, Bengkulu, and Muara Jambi were abundant in gold coins, while silver is rare.
In administered trade system, equivalencies were established between commodities through diplomatic negotiations rather than bargaining.
[1] The gold piloncitos of the Philippines are a late offshoot of the Indonesian gold coinage, while the bean-like silver "namo" series of the Malay peninsula was presumably an offshoot of the silver and may have evolved into the bullet (pod duang) coinage of Sukhothai in Thailand.