The mangosteen isn’t much to look at, sort of a reddish-brown-black with a stem on the top (given how it matches the stone counter, I suppose you could call it stone colored). It reminded me of a persimmon the first time I saw it since there are four leaves at stem, and it’s about the same size. The skin is thick and quite hard, totally unlike a persimmon, though. And, if you’re not careful, the skin will stain things red.
The bottom has this asterisk-shaped thing at the blossom end. Usually there are six arms, plus or minus one or so. This tells you how many segments are on the inside once you cut through the skin, or otherwise break into it.
Like I said, six segments. Usually only one of the segments has a developed seed inside, and all the others are, to all intents and purposes, seedless. This one is unusual since there are two seed segments. That’s actually sort of a minus, since you get more fruit pulp from the segments that aren’t filled with hard seed.
The fruit tastes sort of like monkey apple, but stronger. It’s a sweet-tart-astringent flavor, sort of like tannic lemonade.
The other thing to know about mangosteen is that it goes bad pretty quickly; you can’t keep it around more than a day or two before the fruit inside deliquesces.