Talk:Ringwoodite

Stability

If ringwoodite has been found within meteorites, then clearly it is also stable under normal conditions and not just at high pressure and temperature. I believe that high pressure and temperature are only required for its formation. Tmangray (talk) 19:40, 12 June 2014 (UTC)

Er ... what are the conditions of formation of the meteorite minerals? Seems neither the meteoric ringwoodite nor the one found w/in a diamond were formed under "normal conditions", but rather under high T & P conditions. Seems ringwoodite exists in a metastable state under "normal" Earth surface conditions - as does diamond. Vsmith (talk) 02:36, 14 June 2014 (UTC)

I confess I have no idea what "metastable" means in this context. Diamond seems pretty stable in everyday terms. Sure, the ringwoodite FORMS in meteors under the requisite high TP, but once formed, it's as stable as diamond...isn't it? Tmangray (talk) 03:56, 25 June 2014 (UTC)

Diamond is metastable at STP conditions, too. The point here is that there is a relatively high kinetic (energetic) barrier for the transformation reaction back to the α phase, and the system doesn't have the necessary energy to overcome it at STP conditions. So if you cool ringwoodite fast enough, it doesn't have the time to transform to the low-pressure phase and remains locked in a state that is, in principle, not the energetically favoured one at STP conditions.TomR (talk) 00:27, 25 October 2014 (UTC)

Hydration

Hydrate Ringwoodite contains up to 1.6% water molecules as (Mg0.89,Fe0.11)2SiO4 Hydrate. GEOPHYSICAL RESEARCH LETTERS, VOL. 29, NO. 21, 2021, doi:10.1029/2002GL015276, 2002

Ringwoodite no more "contains" water than does Sodium Hydroxide. I suggest this be corrected to:"Ringwoodite is notable for being able to incorporate water into its structure as hydroxide ions (the hydroxide ion is composed of a single oxygen atom chemically bound to a hydrogen atom, OH^- and having a negative charge).173.189.77.242 (talk) 19:55, 13 June 2014 (UTC)

Modified the "water hype" a bit - could likely use more science and less journalistic hype. Vsmith (talk) 02:25, 14 June 2014 (UTC)

Found

NO one has ever drilled nor found anything 400km down or 600km down. Found is not the word to be used. It's a lie. 75.86.172.174 (talk) 02:53, 3 November 2017 (UTC)

"mantle reservoir is found to contain": shouldnt this be "believed to contain" or "hypothesized/theorized to contain", as we havent "found" it there yet, in the strictest sense.(mercurywoodrose)76.254.38.183 (talk) 16:30, 14 June 2014 (UTC)

I would think this should be moved to a new category about a theory of body of water in the earth underneath the crust. We should be able to test for something like that sometime in the near future,might be able to already with fossil fuel finding tech we already have.

Many articles like this guessing about origin of a matter end up being something different in the end, so im not sure this should be in as a fact for ringwoodite.

Keep this in perspective, all this is based on ONE tiny 40 micrometer spec. — Preceding unsigned comment added by 70.16.210.200 (talk) 10:21, 1 October 2014 (UTC)

There is no "body of water" within the mantle. That one "tiny" crystal of ringwoodite is simply a verification of the high pressure geochemistry/mineral chemistry studies and geophysics/seismic studies of the mantle which indicate the presence of large amounts of hydrogen and hydroxide ions structurally bound within the minerals of the mantle. Vsmith (talk) 13:26, 1 October 2014 (UTC)