Glass vessel sinks are primarily made up of 3 different categories and each has significant different qualities & values. The 3 categories are Slumped, Hand-blown, and Mold-blown. Identifying each can be a challenge to a novice and I always suggest asking a professional in the field of glass to evaluate the sink before you buy.
- A slumped sink is the cheapest of all the sinks and by far the easiest to make. These sinks should be valued at $50-$400 (even though some try to get more than $800!) These typically involve using 2 pieces of window glass heated and “slumped” into a mold to create the shape. Often you will see some type of metallic design or hand-painted design trapped between the two layers of window glass or simply hand-painted on the back side. If you look closely at the edge sometimes you can tell where the two plates came together, but not always. These sinks are the most brittle and can sometimes crack depending of what type of materials was used and how the sink was treated in the cooling or “annealing” process.
- A Mold blown sink is slightly more valuable than a slumped sink and are typically valued at $300-$600. There are two kinds of these mold-blown sinks. Sometimes you will see a sink with a heavy texture on the back side. These are the made by taking the molten glass and simply pressing it into a mold to get its shape and design. The other kind of mold blown sink is typically a machine blown bowl, perfect in shape and most commonly clear. I see a lot of people simply taking these clear machine blown bowls and hand painting the backside with colors/patterns and then clear coating the paint to make it more permanent. The problem with these sinks is the paint is not permanent and can scratch off or fade.
- A Hand-blown sink is the most valuable and most rare. These sinks are typically valued at $1200-$3000. These are truly a work of art for your bathroom! Each is custom made by an artisan in the traditional style of glass blowing. Glass blowing usually is done in a small artist studio with 1 main artist and a few assistants. Glass blowing is a very expensive process whereby an artist melts the glass from raw materials, gathers the glass out of a super-heated crucible (large bowl), and blows the glass using a stainless pipe rolling it back and forth until the desired amount of glass and color is obtained. For more information about hand-blown glass you can visit my website at: SilverLakeStudios.com or ArtGlassSinks.com.