Black Coalish Thing In Orange I recently found a piece of black substance in my Navel Orange. When I rubbed it against my finger, the blacked thing smeared on my finger like coal. It was less the 1 cm wide and kind of look like a jagged piece of gravel. Could anyone know what this could be?
If the substance was soft and smeared easily, as you describe, it was most likely mould - sometimes cells die in a part of the fruit, often through exterior damage, and these rapidly start to decompose. Left long enough, the whole fruit would have gone black. Harmless so long as you don't eat the section that's got black in it, and even if you consumed it, it's only a bit dodgy to eat for people who are mould sensitive.