Pob zeb diamond yog cov ntxhia pob zeb, ib qho ntawm cov nto moo tshaj plaws thiab kim. Muaj ntau ntau speculations thiab legends nyob ib ncig ntawm nws, tshwj xeeb tshaj yog hais txog nws tus nqi thiab nrhiav kom tau ntawm fakes. Ib lub ntsiab lus tshwj xeeb rau kev kawm yog kev sib raug zoo ntawm pob zeb diamond thiab graphite. Ntau tus neeg paub tias cov zaub mov no zoo ib yam, tab sis tsis yog txhua tus paub qhov tseeb. Thiab cov lus nug ntawm yuav ua li cas lawv txawv, ib yam nkaus, tsis yog txhua tus tuaj yeem teb tau. Peb paub dab tsi txog cov qauv ntawm pob zeb diamond? Los yog cov txheej txheem rau kev txiav txim lub pov haum?
pob zeb diamond qauv
Pob zeb diamond yog ib qho ntawm peb cov ntxhia uas yog hloov pauv crystalline ntawm carbon. Lwm ob yog graphite thiab lonsdaleite, qhov thib ob tuaj yeem pom nyob rau hauv meteorites lossis tsim khoom tsim. Thiab yog tias cov pob zeb no yog hexagonal hloov kho, ces hom pob zeb diamond siv lead ua lattice yog lub voos xwmfab. Nyob rau hauv no system, carbon atoms yog teem nyob rau hauv no txoj kev: ib tug ntawm txhua vertex thiab nyob rau hauv nruab nrab ntawm lub ntsej muag, thiab plaub nyob rau hauv lub voos xwmfab. Yog li, nws hloov tawm tiascov atoms yog teem nyob rau hauv daim ntawv ntawm tetrahedra, thiab txhua lub atom nyob rau hauv nruab nrab ntawm ib tug ntawm lawv. Cov khoom sib cuam tshuam los ntawm kev sib cog lus zoo tshaj plaws - covalent, vim tias lub pob zeb diamond muaj qhov nyuaj siab.
tshuaj muaj zog
Hais lus ntxhib, lub pob zeb diamond yog cov pa roj carbon ntshiab, yog li ntawd, pob zeb diamond siv lead ua yuav tsum tau pob tshab kiag li thiab xa txhua lub teeb pom kev. Tab sis tsis muaj dab tsi zoo meej nyob rau hauv lub ntiaj teb no, uas txhais tau hais tias cov ntxhia no kuj muaj impurities. Nws ntseeg tau tias cov ntsiab lus siab tshaj plaws ntawm impurities hauv lub pov haum pob zeb diamond yuav tsum tsis pub tshaj 5%. Cov muaj pes tsawg leeg ntawm lub pob zeb diamond tuaj yeem suav nrog cov khoom thiab cov kua thiab cov roj gaseous, feem ntau ntawm lawv:
- nitrogen;
- boron;
- aluminium;
- silicon;
- calcium;
- magnesium.
Tsis tas li, cov khoom muaj xws li quartz, garnets, olivine, lwm yam minerals, hlau oxides, dej thiab lwm yam khoom. Feem ntau cov ntsiab lus no pom muaj nyob rau hauv cov ntsiab lus ntawm cov ntxhia hauv daim ntawv ntawm cov neeg kho tshuab ntxhia suav nrog, tab sis qee qhov ntawm lawv tuaj yeem hloov cov pa roj carbon hauv pob zeb diamond qauv - qhov tshwm sim no hu ua isomorphism. Hauv qhov no, kev suav nrog tuaj yeem cuam tshuam rau lub cev lub cev ntawm cov ntxhia, nws cov xim, lub teeb pom kev, thiab cov nitrogen suav nrog muab nws cov khoom luminescent.
Lub cev muaj zog
Tus qauv ntawm lub pob zeb diamond txiav txim siab nws lub cev, lawv raug ntsuas raws li plaub yam:
- hardness;
- density;
- dispersion thiab refraction ntawm lub teeb;
- crystal lattice.
Lub hardness ntawm cov zaub mov yog kwv yees ntawm Mohs nplai, nws cov qhab nia ntawm qhov system no yog 10, qhov no yog qhov ntsuas siab tshaj plaws. Cov tom ntej hauv daim ntawv yog corundum, nws qhov taw qhia yog 9, tab sis nws qhov hardness yog 150 npaug tsawg dua, uas txhais tau hais tias qhov zoo tshaj plaws ntawm pob zeb diamond hauv qhov ntsuas no.
Txawm li cas los xij, qhov nyuaj ntawm cov ntxhia tsis txhais tau tias nws lub zog tag nrho. Pob zeb diamond yog nkig heev thiab tawg yooj yim yog tias ntaus nrog rauj.
Lub ntiajteb txawj nqus ntawm pob zeb diamond (qhov ntom) yog txiav txim siab nyob rau hauv thaj tsam ntawm 3.42 txog 3.55 g / cm3. Nws yog txiav txim los ntawm qhov piv ntawm qhov hnyav ntawm cov ntxhia rau qhov hnyav ntawm cov dej ntawm tib lub ntim.
Dhau li ntawm hardness, nws kuj muaj qhov ntsuas siab siab (2.417-2.421) thiab dispersion (0.0574). Qhov kev sib xyaw ua ke ntawm cov khoom no tso cai rau lub pob zeb diamond los ua cov pob zeb zoo tshaj plaws thiab zoo tshaj plaws.
Lwm lub cev lub cev ntawm cov ntxhia kuj tseem ceeb, xws li thermal conductivity (900-2300 W / m·K), kuj yog qhov siab tshaj plaws ntawm tag nrho cov khoom. Koj tseem tuaj yeem nco ntsoov lub peev xwm ntawm cov pob zeb hauv av kom tsis txhob yaj hauv cov kua qaub thiab alkalis, cov khoom ntawm dielectric, qis coefficient ntawm kev sib txhuam rau cov hlau hauv huab cua thiab qhov kub ntawm qhov kub ntawm 3700-4000 ° C ntawm qhov siab ntawm 11 GPa.
Zoo thiab sib txawv ntawm pob zeb diamond thiab graphite
Carbon yog ib qho ntawm cov ntsiab lus ntau tshaj plaws hauv ntiaj teb, nws pom muaj ntau yam khoom, tshwj xeeb tshaj yog nyob rau hauv cov kab mob. Graphite, zoo li pob zeb diamond, yog tsim los ntawm carbon, tab sis cov qauv ntawm pob zeb diamond thiab graphite sib txawv heev. Pob zeb diamond tuaj yeem tig mus rau hauv graphite nyob rau hauv lub zog ntawm qhov kub thiab txias yam tsis muaj kev nkag mus rau oxygen, tab sis nyob rau hauv cov xwm txheej ib txwm muaj, nws muaj peev xwm ua tsis tau.nyob twj ywm tsis hloov, qhov no yog hu ua metastability, ntxiv rau, hom pob zeb diamond siv lead ua lattice yog lub voos xwmfab. Tab sis graphite yog ib txheej pob zeb hauv av, nws cov qauv zoo li cov txheej txheej nyob hauv cov dav hlau sib txawv. Cov khaubncaws sab nraud povtseg yog tsim los ntawm hexagons uas tsim ib lub cev zoo li honeycomb. Cov ntawv cog lus muaj zog tsuas yog tsim los ntawm cov hexagons, tab sis nruab nrab ntawm cov khaubncaws sab nraud povtseg lawv tsis tshua muaj zog, qhov no ua rau cov txheej txheem ntawm cov pob zeb hauv av. Ntxiv rau nws qhov tsis tshua muaj zog, graphite absorbs lub teeb thiab muaj cov xim hlau, uas kuj txawv ntawm pob zeb diamond.
Cov zaub mov no yog qhov piv txwv zoo tshaj plaws ntawm allotropy - qhov tshwm sim uas cov tshuaj muaj cov khoom sib txawv ntawm lub cev, txawm hais tias lawv muaj cov tshuaj tib yam.
Keeb kwm ntawm pob zeb diamond
Tsis muaj kev xav tsis meej txog yuav ua li cas pob zeb diamond tsim nyob rau hauv qhov xwm txheej, muaj magmatic, mantle, meteorite thiab lwm yam kev xav. Txawm li cas los xij, feem ntau yog magmatic. Nws ntseeg tau tias pob zeb diamond yog tsim nyob rau hauv qhov tob ntawm txog 200 km nyob rau hauv lub siab ntawm 50,000 atmospheres, thiab ces coj mus rau saum npoo nrog rau magma thaum lub sij hawm tsim ntawm kimberlite kav. Lub hnub nyoog ntawm pob zeb diamond txawv ntawm 100 lab mus rau 2.5 billion xyoo. Nws kuj tau raug tshawb fawb pov thawj tias pob zeb diamond tuaj yeem tsim tau thaum lub meteorite tsoo lub ntiaj teb saum npoo, thiab tseem tuaj yeem pom hauv pob zeb meteorite nws tus kheej. Txawm li cas los xij, crystals ntawm lub hauv paus chiv keeb no me me heev thiab tsis tshua haum rau kev ua.
pob zeb diamond deposits
thawj qhov tso nyiaj uas yogPob zeb diamond tau pom thiab mined, nyob rau hauv Is Nrias teb, tab sis thaum kawg ntawm lub xyoo pua 19th lawv tau depleted heev. Txawm li cas los xij, nws tau nyob ntawd uas cov qauv nto moo tshaj plaws, loj thiab kim tau raug mined. Thiab nyob rau hauv 17th thiab 19th centuries, mineral deposits tau pom nyob rau hauv Brazil thiab South Africa. Keeb kwm yog tag nrho nrog cov lus dab neeg thiab qhov tseeb txog lub pob zeb diamond maj, uas cuam tshuam tshwj xeeb nrog South African mines. Qhov kawg pom pob zeb diamond deposits yog nyob rau hauv Canada, lawv txoj kev loj hlob pib tsuas yog nyob rau hauv lub xeem xyoo caum ntawm lub xyoo pua 20th.
Cov mines ntawm Namibia yog qhov nthuav tshwj xeeb, txawm hais tias pob zeb diamond mining muaj kev lag luam nyuaj thiab txaus ntshai. Deposits ntawm crystals yog concentrated nyob rau hauv ib txheej ntawm cov av, uas, txawm hais tias nws complicates txoj hauj lwm, hais lus ntawm high quality ntawm minerals. Pob zeb diamonds uas tau taug kev ob peb puas kilometers mus rau saum npoo nrog kev sib txhuam tsis tu ncua tiv thaiv lwm cov pob zeb yog qib siab, qis-zoo crystals tsis tuaj yeem tiv taus qhov kev taug kev, thiab yog li ntawd 95% ntawm cov pob zeb mined yog lub pov haum zoo. Kuj tseem muaj cov kav dej kimberlite uas paub zoo thiab nplua nuj nyob hauv Russia, Botswana, Angola, Guinea, Liberia, Tanzania thiab lwm lub tebchaws.
pob zeb diamond processing
Kev ua pob zeb diamond yuav tsum muaj kev paub zoo, kev paub thiab kev txawj ntse. Ua ntej pib ua haujlwm, nws yog ib qho tsim nyog yuav tsum tau ua tib zoo kawm lub pob zeb txhawm rau txhawm rau khaws nws qhov hnyav ntau li ntau tau thiab tshem tawm cov kev suav nrog. Feem ntau hom pob zeb diamond txiav yog puag ncig, nws tso cai rau lub pob zeb ci ntsa iab nrog txhua yam xim thiab pom lub teeb pom kev zoo li qhov ua tau. Tab sis txoj haujlwm no kuj yog qhov nyuaj tshaj plaws:lub pob zeb diamond puag ncig muaj 57 lub dav hlau, thiab thaum txiav nws, nws yog ib qho tseem ceeb uas yuav tsum tau saib xyuas qhov tseeb tshaj plaws proportions. Tsis tas li ntawd nrov hom kev txiav yog: oval, teardrop, lub plawv, marquise, emerald thiab lwm yam. Muaj ob peb theem ntawm kev ua ntxhia:
- markup;
- splitting;
- sawing;
- ncig;
- ncig.
Nws tseem ntseeg tias tom qab ua tiav, lub pob zeb diamond poob li ib nrab ntawm nws qhov hnyav.
pob zeb diamond ntsuam xyuas
Thaum pob zeb diamond raug mined, tsuas yog 60% ntawm cov pob zeb tsim nyog rau kev ua, lawv hu ua cov hniav nyiaj hniav kub. Lawm, tus nqi ntawm pob zeb ntxhib yog qis dua tus nqi ntawm pob zeb diamond (ntau tshaj ob zaug). Pob zeb diamond muaj nuj nqis raws li 4C system:
- Carat (qhov hnyav carat) - 1 carat sib npaug 0.2 g.
- Xim (xim) - pob zeb diamond dawb huv yuav luag tsis pom, feem ntau cov ntxhia muaj qhov ntxoov ntxoo. Nws cov nqi feem ntau nyob ntawm cov xim ntawm lub pob zeb diamond, feem ntau ntawm cov pob zeb pom nyob rau hauv qhov muaj cov xim daj lossis xim av, paj yeeb, xiav thiab ntsuab pob zeb tuaj yeem pom tsawg dua. Qhov tsawg tshaj plaws, zoo nkauj, thiab yog li kim yog cov zaub mov ntawm cov xim saturated, lawv hu ua fantasy. Qhov tsawg tshaj plaws yog ntsuab, ntshav thiab dub.
- Clarity (clarity) kuj yog ib qho tseem ceeb qhia uas txiav txim seb muaj cov tsis xws luag nyob rau hauv lub pob zeb thiab ho cuam tshuam nws tus nqi.
- Cut (txiav) - qhov pom ntawm pob zeb diamond nyob ntawm qhov txiav. Refraction thiab reflection ntawm lub teebib hom "ci ntsa iab" ci ntsa iab ua rau lub pob zeb no muaj txiaj ntsig, thiab cov duab tsis zoo lossis qhov sib piv ntawm qhov sib npaug thaum ua tiav tuaj yeem rhuav tshem nws.
Tsim cov pob zeb diamond
Tam sim no thev naus laus zis tso cai rau koj "loj hlob" pob zeb diamond, yuav luag tsis paub qhov txawv ntawm ntuj. Muaj ntau txoj hauv kev los ua ke:
- Tsim HPHT-pob zeb diamond yog txoj kev ze tshaj plaws rau tej yam ntuj tso. Minerals yog tsim los ntawm graphite thiab noob pob zeb diamond ntawm qhov kub ntawm 1400 ° C nyob rau hauv lub siab ntawm 50,000 atmospheres. Txoj kev no tso cai rau koj los tsim cov pob zeb zoo nkauj.
- Tsim CVD-pob zeb diamond (zaj duab xis synthesis) - kev tsim cov pob zeb hauv lub tshuab nqus tsev siv cov noob thiab methane thiab hydrogen gases. Txoj kev no ua rau nws muaj peev xwm los tsim cov pob zeb ntshiab, txawm li cas los xij, lawv muaj qhov me me, yog li lawv tsuas yog siv rau kev lag luam.
- Explosive fusion yog ib txoj hauv kev uas tsim cov pob zeb diamond me me los ntawm kev tawg cov khoom tawg thiab tom qab ntawd txias cia.
Yuav ua li cas paub qhov qub ntawm tus cuav
Hais txog txoj hauv kev los txiav txim siab qhov tseeb ntawm pob zeb diamond, nws tsim nyog paub qhov txawv ntawm kev txheeb xyuas qhov tseeb ntawm pob zeb diamond thiab pob zeb diamond ntxhib. Ib tus neeg tsis paub qab hau tuaj yeem cuam tshuam lub pob zeb diamond nrog quartz, siv lead ua, lwm yam pob zeb pob tshab, thiab txawm tias iav. Txawm li cas los xij, qhov tshwj xeeb ntawm lub cev thiab tshuaj lom neeg ntawm lub pob zeb diamond ua rau nws yooj yim pom qhov cuav.
BUa ntej ntawm tag nrho cov, nws yog tsim nyog nco ntsoov lub hardness. Lub pob zeb no tuaj yeem khawb txhua qhov chaw, tab sis tsuas yog lwm lub pob zeb diamond tuaj yeem tso cov cim rau ntawm nws. Tsis tas li ntawd, perspiration tsis nyob twj ywm ntawm lub ntuj siv lead ua yog tias koj ua pa rau nws. Ntawm lub pob zeb ntub dej, yuav muaj lub cim zoo li xaum yog tias koj khiav aluminium hla nws. Koj tuaj yeem tshawb xyuas nws nrog x-ray: lub pob zeb ntuj nyob hauv hluav taws xob muaj xim ntsuab nplua nuj. Los yog saib los ntawm nws ntawm cov ntawv nyeem: nws yuav tsis yooj yim sua kom ua nws los ntawm lub ntuj pob zeb diamond. Cais, nws tsim nyog sau cia tias lub ntuj tsim ntawm lub pob zeb tuaj yeem kuaj xyuas qhov cuam tshuam ntawm lub teeb: nqa qhov qub mus rau lub teeb ci, koj tuaj yeem pom tsuas yog lub teeb pom kev hauv nruab nrab.
