Afourer mandarins are commonly grown in Australia, and certain growing regions are extremely warm in summer, and rain is seldom.
These mandarins are of high red orange colour. They are very easy to peel, and the segments separate easily. They have very good flavour that is sweet and tangy at the same time, and are very juicy. These fruits are also nearly seedless.
An inherent characteristic of Afourer mandarins is that sometimes it develops amber coloured, gummy droplets in the core of the fruit.
Gumming occurs when there are extremely hot growing conditions and is caused by the tearing of the white core tissue of the fruits and tiny drops of juice crystalize to form dark brown sugar drops. Ironically, the same conditions are responsible for the development of the sweet tasting fruit. They are not caused by insects or disease, and are totally natural and harmless.
Simply remove the gum spots, and they are still safe to eat!