 | | | | Crystallite growth kinetics in nanocrystalline quartz (agate and chalcedony) T. MOXON1,* 1 2 AND M. A. CARPENTER2...2009] ABSTR ACT Crystallite growth in natural agate samples has been investigated at temperatures of...size prior to 8 9 growth inhibition: Co Cs þ ln:Cm Co ; ¼ kt. Co = initial crystallite size, Cs = crystallite...at 550ºC. Limited growth was obtained when small agate cubes were heated in an open furnace up to 122 d...crystallite growth rate law does not describe natural agate growth quantitatively but a qualitatively similar |  | | Journal (article/letter/editorial) | | Magazine, October 2006, Vol. 70(5), pp. 485–498 Agate and chalcedony from igneous and sedimentary hosts...fibrous and granular regions of these agates. One agate shows a partial transformation of the petrographic...in agate could serve as an indicator of palaeoheating within the parent rock. K EY WORDS : agate, chalcedony...is known as agate. Agate with banding in concentric zones is defined as walllining agate. The banding...crystallization process and textural changes. Less often, agate appears as horizontal banding that is presumed to |  | | Journal (article/letter/editorial) | | Vol. 71(4), pp. 461–476 Metamorphic effects on agate found near the Shap granite, Cumbria, England: as...3.48 Ga metamorphosed hosts found in Western Australia were similar but different from agates found in...Ma and those from Stockdale Beck and Western Australia. Agates from the latter areas have a lower proportion...and Western Australian agates demonstrate that an agate or chalcedony infill can be used to identify post-deposition...palaeoheating within a host rock. K EY WORDS : agate, chalcedony, moganite, IR, Raman, XRD, cathodoluminescence |  | | Journal (article/letter/editorial) | | 1223–1244 A re-examination of water in agate and its bearing on the agate genesis enigma TERRY MOXON 55 Common...atmospheric water vapour pressure conditions. After agate acclimatization at 20°C and 46% relative humidity...problems have consequences for water quantification in agate and chalcedony using infrared or thermogravimetric...thermogravimetric techniques. Mobile and total water in agate is considered in relation to host-rock age, mogánite...development and agate genesis. The water data also supports previous claims that agates from New Zealand and |
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