Diospyros virginiana In respect to the power of making heartwood, the persimmon rarely develops any heartwood until it is nearly one hundred years old. This heartwood is extremely close-grained and almost black, resembling ebony (of which it is a true variety). It is a common misconception persimmon fruit needs frost to ripen and soften, called bletting. Some, such as the early-ripening varieties "pieper" and "NC21"(also known as "supersweet"), easily lose astringency and become completely free of it when slightly soft at the touch—these are then very sweet, even in the British climate. On the other hand, some varieties (like the very large
Diospyros ebenum organized and wavy. Dry wood density is 1190 kg/m3. The tree is occurring in southern India, Sri Lanka and Indonesia. The variety of the wood found in North Sulawesi, Indonesia is "Diospyros ebenum Koenig". Known as කළුවර ගස් ("Kaluwara Gas") by Sinhalese people due to hard black wood of the tree. In Sri Lanka, it is illegal to harvest and sell ebony wood. It possesses the following valuable qualities: high wood hardness (twice as hard as oak), easy to polish (suitable for high-quality polishing, after which it becomes perfectly smooth), it has practically no pitting, provides glossy smooth surface, water