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The formation mechanisms of Polycrystalline diamonds : diamondites and carbonados

Aguilera Pradenas, Ariam LU (2015) In Dissertations in Geology at Lund University GEOL01 20151
Department of Geology
Abstract
Diamond is a cubic carbon mineral that possess many unique characteristics like extreme hardness and thermal conductivity. There are many types of diamonds like monocrystalline, polycrystalline and coated/ fibrous and in this bachelor thesis the focus was on polycrystalline diamonds; carbonado and diamondites (are divided in three different types of diamonds: eclogitic, perioditic -and websteritic-type). I made a literature study on the formation mechanism of diamondites to see whether they have different crystallisation histories than monocrystalline diamonds as some researchers argue. Determing a relationship, or lack thereof, between monocrystalline diamonds and diamondites could be valuable to the mining industry. I also made a... (More)
Diamond is a cubic carbon mineral that possess many unique characteristics like extreme hardness and thermal conductivity. There are many types of diamonds like monocrystalline, polycrystalline and coated/ fibrous and in this bachelor thesis the focus was on polycrystalline diamonds; carbonado and diamondites (are divided in three different types of diamonds: eclogitic, perioditic -and websteritic-type). I made a literature study on the formation mechanism of diamondites to see whether they have different crystallisation histories than monocrystalline diamonds as some researchers argue. Determing a relationship, or lack thereof, between monocrystalline diamonds and diamondites could be valuable to the mining industry. I also made a literature study on the origin of carbonado because carbonados are important as abrasives in the industries. Constraining an origin for carbonados would give us valuable knowledge about their formation mechanisms, could help us to make synthetic carbonado which could be cheaper than prospecting for natural carbonado. Several origins for carbonado are proposed which are for example meteorite impact, uranium-rich carbonaceous sediments and mantle. The most likely origin is the mantle which is supported among others by textural observations (for example fluid inclusions) but to determine this with certainty a carbon-source needs to be identified in the mantle and komatiite related carbonados. Two different crystallization histories are proposed for diamondites which are; fluids/melts derived from upper mantle or fluids/melts that had a contribution of crustal material. At the moment it is more likely that the formation fluids of E -and P-type diamondites are derived from the upper mantle because there are more evidence that is consistently supported by both eclogitic -and perioditic diamondites. Regarding the websteritic diamondites their formation fluids are more likely to have a crustal origin as all evidence suggest this origin (Less)
Popular Abstract (Swedish)
Det finns många typer av diamanter som till exempel monokristallina, polykristallina och belagda/fibrösa, vilka har egna karaktäristiska drag. Polykristallina diamanter kan delas in i två huvudgrupper carbonado och diamonditer, som i sin tur delas in i 3 typer; eclogitic, perioditic -and websteritic. Litteratur studien består av två delar, i den första delen undersöks bildningsmekanismen av diamonditer för att se om de har annorlunda kristalliserings mekanism än monokristallina diamanter. Förståelse för denna process kan vara viktig inom gruvindustrin. Den andra delen granskade härkomsten av carbonado som är viktiga inom industrin för slipmedel. Olika härkomster för carbonado har föreslagits bland annat meteoritnedslag, uranium-rika... (More)
Det finns många typer av diamanter som till exempel monokristallina, polykristallina och belagda/fibrösa, vilka har egna karaktäristiska drag. Polykristallina diamanter kan delas in i två huvudgrupper carbonado och diamonditer, som i sin tur delas in i 3 typer; eclogitic, perioditic -and websteritic. Litteratur studien består av två delar, i den första delen undersöks bildningsmekanismen av diamonditer för att se om de har annorlunda kristalliserings mekanism än monokristallina diamanter. Förståelse för denna process kan vara viktig inom gruvindustrin. Den andra delen granskade härkomsten av carbonado som är viktiga inom industrin för slipmedel. Olika härkomster för carbonado har föreslagits bland annat meteoritnedslag, uranium-rika kolhaltiga sediment och manteln. För närvarande teorin som är mest sannolikt är manteln som stödjs av texturella observationer såsom fluid inklusioner och kristallografisk riktning. För att kunna veta att denna teori stämmer med säkerhet behöver man hitta en kolkälla i manteln och komatiite relaterade carbonados. Två olika kristalliserings mekanismer föreslås för diamonditer vilka är; fluider/smältor som härstammade från övre mantel eller fluider/smältor som hade ett bidrag från jordskorpans material. För närvarande är det mest troligt att bildnings fluiderna för E -and P-typ diamonditer härstammar från övre manteln. Vad gäller websteritic diamonditer bildades de från övre mantel fluider (Less)
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author
Aguilera Pradenas, Ariam LU
supervisor
organization
alternative title
Bildningsmekanismerna för Polykristallina diamanter : diamonditer och carbonados
course
GEOL01 20151
year
type
M2 - Bachelor Degree
subject
keywords
polycrystalline, diamondite, carbonado
publication/series
Dissertations in Geology at Lund University
report number
459
language
English
id
8055753
date added to LUP
2015-10-20 10:24:51
date last changed
2017-10-12 04:09:47
@misc{8055753,
  abstract     = {Diamond is a cubic carbon mineral that possess many unique characteristics like extreme hardness and thermal conductivity. There are many types of diamonds like monocrystalline, polycrystalline and coated/ fibrous and in this bachelor thesis the focus was on polycrystalline diamonds; carbonado and diamondites (are divided in three different types of diamonds: eclogitic, perioditic -and websteritic-type). I made a literature study on the formation mechanism of diamondites to see whether they have different crystallisation histories than monocrystalline diamonds as some researchers argue. Determing a relationship, or lack thereof, between monocrystalline diamonds and diamondites could be valuable to the mining industry. I also made a literature study on the origin of carbonado because carbonados are important as abrasives in the industries. Constraining an origin for carbonados would give us valuable knowledge about their formation mechanisms, could help us to make synthetic carbonado which could be cheaper than prospecting for natural carbonado. Several origins for carbonado are proposed which are for example meteorite impact, uranium-rich carbonaceous sediments and mantle. The most likely origin is the mantle which is supported among others by textural observations (for example fluid inclusions) but to determine this with certainty a carbon-source needs to be identified in the mantle and komatiite related carbonados. Two different crystallization histories are proposed for diamondites which are; fluids/melts derived from upper mantle or fluids/melts that had a contribution of crustal material. At the moment it is more likely that the formation fluids of E -and P-type diamondites are derived from the upper mantle because there are more evidence that is consistently supported by both eclogitic -and perioditic diamondites. Regarding the websteritic diamondites their formation fluids are more likely to have a crustal origin as all evidence suggest this origin},
  author       = {Aguilera Pradenas, Ariam},
  keyword      = {polycrystalline,diamondite,carbonado},
  language     = {eng},
  note         = {Student Paper},
  series       = {Dissertations in Geology at Lund University},
  title        = {The formation mechanisms of Polycrystalline diamonds : diamondites and carbonados},
  year         = {2015},
}