You can learn more about diamonds and their visual dazzle, below.
Uncut unshaped diamonds look like shiny black coal
Black diamonds are diamonds, but they are black, and not transparent. Follow the link, below, to see photos of black diamonds.
Diamonesk diamonds are not real diamonds. They are stones that are made to look like real diamonds. They are a brand of diamond ring.
Faceted, finished brown diamonds are simply diamonds within that colour range. Chocolate diamonds are an intense brown colour.
Out of the ground they look like little rocks/crystals. It is only when they are cut and polished that they look like they do in a ring.
when diamonds come out of the ground they are rough and not as pretty as in jewelery stores
They look like cyan (light-blue) crystals of some sort.
Jewelery can contain real diamonds, and jewelery can contain other gems, including stones meant to look like diamonds.
They are only in the 1.3.1 update and you have to look for them like you have to look for diamonds :P
Appearance wise, diamonds feel like they have an oily film on them which prevents them from being dirty. They also have a metallic luster like new steel or lead. They will not be clear like glass and are translucent. You can typically see into them but not through them.
Because of their lights on the wings and cabin.
Not everyone wants diamonds. Some people do, but you can't say everyone does. Some think diamonds are pretty. Some like them because good ones are valuable. Some people don't like them because they look like expensive glass.