Which of the following is not true about the weights of the Harappan period?

The weights were usually made of a stone called carnelian.

Weights of the Harappan Culture:

The Harappans had a well-regulated system of exchanges that involved the use of precise weights.
The weights used in trade were typically made of chert & were cubical in shape without any markings.
The lower denominations of weights followed a binary system, including values such as 1, 2, 4, 8, 16, 32, and so on, up to 12,800.
On the other hand, the higher denominations of weights followed the decimal system.
The smaller weights were likely used specifically for weighing items like jewelry and beads.
In addition to the weights, metal scale-pans have also been discovered, indicating the presence of a comprehensive weighing system during the Harappan civilization.