In 1961, the Italian artist Piero Manzoni filled 90 tin cans with his feces, labeled it Artists Sh*t and sold them according to their equivalent weight in gold. Many of the cans have since exploded due to decomposition producing gas inside the sealed tins. Apparently this makes the price of the remaining cans go up because they are rarer, so its worth way more than its weight in gold now, each containing 30g of poop worth 100k USD today.
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