The four-inch square patches can then be joined together using Velcro that contains silver-coated contacts to enable electrical connectivity.

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Tiny particles of silver are coated with organic molecules so that they float, and are then added to silicone oil.

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The most popular gift is mithai (Indian sweets), and shops are filled with a spectacular array specially prepared for this festival, from thickly cut squares of barfi (a fudge-like sweet, often coated with a thin film of edible silver leaf) , to soft syrupy gulab jamuns (deep-fried balls of dough) and spongy rasgullas (sweetened cream cheese balls flavoured with rose water).

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