This bathroom copper sink has a standard 1.5 diameter hole and it does not have an overflow system. It is designed for above-the-counter mounting because the border is rounded. The copper sheet is 16 gauge (0.05" thickness). This hammered bathroom copper sink is a beautiful piece of art. The wise artisan's hands transform it from a copper sheet into this unique piece. The hammer footprint is very visible. The reddish/oxidized texture is characteristic of natural copper when it is cooled from red-hot temperature using cold water, the technique that the copper-smiths use. This copper sink was made from one sheet of copper, raised with the artist's hammer, there are no welded joints.Hammering the red-hot copper is an ancient technique the copper-smiths use, where no sophisticated tools are used. The only equipment used is the furnace to heat the copper and a hammer to give it its shape. This bathroom copper sink is from the skilled copper-smiths of Santa Clara del Cobre, Mexico. The finish is a dark brownish color. Suitable for your bathroom, it will add a unique home accent making it a very special point of attraction. IMPORTANT NOTE: The patina can be damaged faster if toothpaste stays for long periods of time on the sink surface, because of this, washing it after brushing teeth is recommended."