'Diamond rain' falls on Saturn and Jupiter

reply to post by Yngvarr

As far as I know, the composition of the core of Jupiter is still somewhat speculative. However, if you want to venture an educated guess on the composition, why wouldn't you look at the composition of material in the asteroid belt between Mars and Jupiter? We believe that meteorites that fall to Earth consist largely of samples from that asteroid belt that have been disturbed from their orbit through collisions or gravitational disturbances, so if the core of Jupiter has any similarity to the composition of the asteroid belt, then we could guess at the composition of the core of Jupiter. There are notable amounts of carbon, which could form diamond, but I don't think it's the dominant material, as there are lots of other substances like silicates, and even a little bit of Iron.

I ran across a hypothesis that some diamonds may have "rained" on Earth billions of years ago, but it's only a hypothesis as the origin of the diamonds found in "carbonado" is uncertain.

Carbonado

Carbonado diamonds are typically pea-sized or larger porous aggregates of many tiny black crystals. The most characteristic carbonados have been found only in the Central African Republic and in Brazil, in neither place associated with kimberlite, the source of typical gem diamonds. Lead isotope analyses have been interpreted as documenting crystallization of carbonados about 3 billion years ago. The carbonados are found in younger sedimentary rocks.

Mineral grains included within diamonds have been studied extensively for clues to diamond origin. Some typical diamonds contain inclusions of common mantle minerals such as pyrope and forsterite, but such mantle minerals have not been observed in carbonado...

Extraterrestrial origin hypothesis

Supporters of an extraterrestrial origin of carbonados, such as Dr. Stephen Haggerty, a geoscientist from Florida International University, propose that their material source was a supernova which occurred at least 3.8 billion years ago. After coalescing and drifting through outer space for about one and a half billion years, a large mass fell to earth as a meteor approximately 2.3 billion years ago, possibly fragmenting during entry into the Earth's atmosphere, and impacting in a region which would much later split into Brazil and the Central African Republic, the only two known locations of carbonado deposits.