We do not have detailed information about the age and the context of the general use of these weights, but they are probably similar to those used in the Portuguese territory since the start of the nationality.
We know that in the Middle Ages stone weights were used to weigh wool and linen.
The “stone” would have been the equivalent of 8 arráteis.
Several monarchs (namely King João I) would come to proscribe the use of weights made from stone, but they continued to be used by the populace until the middle of the 19th century, when the old measurement systems were replaced by the metric system.
In this conformity, and despite the royal decrees to the contrary, and the dissemination of and preference given to weights made of metal, we can still find weights made of stone (granite in particular) in the middle of the 19th century, which were used to weigh a variety of products, including wax and straw.