The ablution cup is, as its name implies, a small vessel for water in which the priest washes his fingertips to cleanse them before touching the consecrated elements either during the Mass or extra missam. Used at the altar, it was complemented by a plate and a tiny linen cloth for drying the hands. Most such basins were made of glass or, preferably, silver, which was considered to be a nobler material.
Ablution cups usually had a lid and also a small plate underneath, to which they were sometimes attached. When made of silver, each of the three elements was embellished with engraved symbolic representations, generally of plant motifs. The pattern and treatment process of this one make it an excellent example of late 18th century Indo-Portuguese art.