Contrastaria, an official service affiliated with INCM - Imprensa Nacional Casa da Moeda, ensures the verification and hallmarking of precious metal products with complete impartiality, protecting consumers from counterfeits and guaranteeing fair competition between economic agents in the sector.

The Contrastaria service arose from the need to control and label products made from precious materials and is considered the oldest consumer protection measure.

Only Contrastaria can mint a hallmark that certifies the type of metal from which the piece is made and the density of gold in the piece.