Re: Dense diamond @ Grikath - nuclei not collapsed but electron shells are
As we all know normal matter is mostly empty space between the nucleus of an atom and its electron shell(s) and the also between the shells.
The so called diamond at the heart of this white dwarf would be extremely dense as a white dwarf is made of electron degenerate matter (collapsed matter) and while the carbon nuclei may be intact (so it is still the element carbon by proton and neutron count) the electron shells are compressed and changed so the nuclei can sit much closer to each other, not held really far apart by normal interacting electron shells. As the article states just over one solar mass in a spheroid the size of the earth. Density is around 1,000Kg per cubic centimetre. Bit heavy for even the average engagement ring!
Doubtful that the carbon nuclei are in tetrahedral diamond configuration as all molecular/crystalline formation are governed by electron shell interactions.