7-Metal Tibetan Singing Bowl

A 7-metal singing bowl is primarily composed of copper and tin, with the other metals added in trace amounts when present. It is a bell bronze, meaning an alloy containing approximately 77% to 80% copper and 20% to 23% tin, like the bronze used for bells, gongs, and cymbals. According to analyses of more than one hundred Himalayan bowls made between the 16th and 19th centuries, this bronze is almost always present, with traces of iron found in a small number of them. However, each bowl has its own composition because iron and, more rarely, lead or mercury are present in varying proportions. Lead may accompany tin, while gold and silver may accompany copper in small quantities as naturally occurring components of the ore.

Artisans keep the exact proportions of their alloys secret, passing them down from one generation to the next. This is why the proportion of each metal is not listed for the bowls in this collection.

The alloy gives your bowl its hardness, which determines how long the note lasts and the richness of its overtones. Bronze becomes harder and more rigid when its tin content exceeds 20%, allowing the note to sustain longer.

However, the alloy is not the only factor to consider because the sound also depends on the wall thickness, the bowl’s weight, the shape of the rim, and the hammering. The sound is more closely related to the ratio of copper to tin than to the metals added in trace amounts. Opinions are divided when it comes to sound: just as many people find their 7-metal bowl more harmonious than a bronze bowl as find the opposite. We therefore recommend choosing by ear.

The price of a 7-metal singing bowl varies mainly depending on its diameter and the amount of work done by hand. If a bowl is available in multiple sizes, the largest will cost more than the smallest.

The manufacturing method also matters because a hand-hammered bowl costs more than a cast or machine-made one. You are paying for the artisans’ labour and a one-of-a-kind piece that cannot be reproduced exactly. The same applies to a bowl that has been tested and recorded before being offered for sale.

To care for a 7-metal singing bowl, simply wipe it with a soft, dry cloth after each use. Fingerprints and skin oils are the primary causes of tarnishing. We recommend wiping the rim last because the bowl sings when the mallet rubs against this area, and an oily rim will cause the mallet to slip. From time to time, you can wash your instrument with lukewarm water and a drop of mild soap, provided that you never let it soak and dry it immediately to prevent water spots and oxidation. Avoid abrasive products, scouring pads, and the dishwasher. Lemon, vinegar, and metal polishes alter the metal’s surface and are unsuitable if you want to preserve the patina or an engraving.

Over time, your bowl will darken. This alloy patina is part of the instrument’s character and does not affect its sound. If you notice greenish spots, they come from the copper oxidising in moisture. You should therefore store your bowl in a dry place on its cushion without stacking it on another bowl. Finally, avoid dropping it on a hard floor because this tin-rich bronze can crack.

The difference lies in the bowl’s wall, which is irregular on a hammered bowl and even on a cast bowl, changing the instrument’s sound and appearance.

In the first case, the molten alloy is cast into a thick disc. The disc is then heated over a fire and rhythmically hammered by several blacksmiths while another holds it with tongs. It must be reheated throughout the process to prevent the cold metal from cracking under the hammer. Once the bowl is finished, its wall is slightly thicker in some places and thinner in others. As a result, these areas vibrate at slightly different rates, producing more overtones and a sound unique to each bowl.

In the second case, the molten metal is generally poured into a mould, often made of sand, that may already contain patterns. The mould must then be broken once the metal has cooled. Any imperfections must be corrected by hand before the bowl is chiselled and polished. Its even wall produces a clearer, more stable note, while also making it easier to create fine engravings and repeated patterns.

In both cases, you will receive genuine instruments suited to your practice. Some bowls are also cast into an initial shape and then hammered, engraved, and polished by hand.