A few months ago, I saw an image of that kind of apple and thought it was burnt.Have you guys heard of the Black Diamond Apple?
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The Black Diamond Apple is a rare breed from the family of Hua Niu apples that is cultivated in the Tibetan region of Nyingchi. Despite what the name suggests, the apple rather is a purple hue, with white pulp on the inside. Its unique color is due to the region's high altitude. Wikipedia