Gauge/Quality of the Metal - When comparing different sinks, the gauge of the metal is one of the most important factors involved. The gauge and quality of the sink’s material will greatly impact the durability, longevity, and overall wear and tear of the sink - more so than anything else. The lower the gauge, the thicker the metal. The higher the gauge, the more prone the sink is to warping, denting, cracking, etc. Low quality sinks are usually coated with a lacquer or clear coat, because the metal will quickly deteriorate without it. After this coating wears off (which it inevitably will), the sink is easily scratched. This is common with imported sinks, and can easily turn your kitchen sink into an eye sore. If a sink is coated, the metal will contain impurities, recycled material, and other potentially harmful alloys such as arsenic.
Recycled vs. non-recycled - Perhaps one of the most important factors to consider is wether or not the sink’s is made from recycled material. The majority of sinks in the industry are made from recycled copper or stainless steel, which is why they have a limited lifespan, limited warranty, and overall dull appearance. Recycled metals originate from alloys that have been mixed with chemicals and other impurities - resulting in a product that will need to be dried, waxed, and heavily maintained. Investing in a sink that is made from a pure non-recycled material is more expensive, however replacing a failed sink (along with countertops and/or cabinetry) will be much more expensive in the long run.
Sinks with Clear Coat/Lacquer/Protectant - Sinks with a protective coating on them, known as clear coat or lacquer, are widely available in the kitchen & bath industry. The reason manufacturers do this is because they use a low quality (usually recycled) material, which in it’s raw form will not hold up against normal wear and tear. The protective coating will wear thinner with every use, inevitably resulting in an easily scratched surface which will rust and wear out when left unprotected. As a general rule of thumb, if a metal is coated - it has a short lifespan and leads to large amounts of cleaning and maintenance.
Dimensions may vary - One of the biggest concerns when purchasing a sink is the exact specifications. The tolerance of most imported sinks is typically 1/2”, which is completely unacceptable - dimensions should never vary more than 1/32".
Type of Material - For stainless steel sinks, the most common types of stainless used are type 301, type 304 and type 316. The differences between these metals are important, considering what a kitchen sink is used for. Type 316 stainless has an elevated performance, and is considered the golden standard in the food and restaurant equipment industry. Also, it is primarily used in hospital and healthcare applications. Type 301 stainless is specifically designed to be a cheaper alternative, with lower levels of chromium, nickel, and significantly more carbon content. This means type 301 will inevitably corrode faster, scratch easier, and require extreme maintenance down the road.
For copper sinks, evaluating the material is slightly different. The quality of copper is best determined based on thickness of the metal, and whether or not the material is recycled copper. Realistically, high quality copper will last for centuries. The purity rating has a dramatic impact on the life expectancy of the metal. The best quality copper sinks are made from 48 oz cold-rolled, non-recycled, 99.9% pure, 14-gauge copper. Inferior copper is potentially susceptible to tarnishing, rusting, warping, and cracking. Many importers are known to clear coat and lacquer their copper finish, as it is low grade.