检索结果-南通市图书馆

Round Top Mountain rhyolite(Texas, USA), a massive, unique Y-bearing-fluorite-hosted heavy rare earth element(HREE) deposit

引用

Journal of Rare Earths 2014年第1期32卷 90-96页

作者： PINGITORE Nicholas CLAGUE Juan gorski daniel Department of Geological Sciences The University of Texas at El Paso Texas Rare Earth Resources

Round Top Mountain in Hudspeth County, west Texas, USA is a surface-exposed rhyolite intrusion enriched in Y and heavy rare earth elements （HREEs）, as well as Nb, Ta, Be, Li, F, Sn, Rb, Th, and U. The massive tonnage, estimated at well over 1 billion tons, of the deposit makes it a target for recovery of valuable yttrium and HREEs （YHREEs）, and possibly other scarce ele-ments. Because of the extremely fine grain size of the mineralized rhyolite matrix, it has not been clear which minerals host the YHREEs and in what proportions. REE-bearing minerals reported in the deposit included bastn？site-Ce, Y-bearing fluorite, xeno-time-Y, zircon, aeschynite-Ce, a Ca-Th-Pb fluoride, and possibly ancylite-La and cerianite-Ce. Extended X-ray absorption fine struc-ture （EXAFS） indicated that virtually all of the yttrium, a proxy for the HREEs, resided in a coordination in the fluorite-type crystal structure, rather than those in the structures of bastn？site-Ce and xenotime-Y. The YREE grade of the Round Top deposit was just over 0.05%, with 72%of this consisting of YHREEs. This grade was in the range of the South China ionic clay deposits that supply essentially all of the world’s YHREEs. Because the host Y-bearing fluorite is soluble in dilute sulfuric acid at room temperature, a heap leaching of the deposit appeared feasible, aided by the fact that 90%-95%of the rock consists of unreactive and insoluble feld-spars and quartz. The absence of overburden, remarkable consistency of mineralization grade throughout the massive rhyolite, prox-imity （a few km） to a US interstate highway, major rail systems and gas and electricity, temperate climate, and stable political location in the world’s largest economy all enhanced the potential economic appeal of Round Top.

关键词： heavy rare earth elements yttrium-beating fluorite yttrofluorite heap leaching rhyolite Round Top deposit

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Using yttrium as an indicator to estimate total rare earth element concentration:a case study of anthracite-associated clays from northeastern Pennsylvania

引用

International Journal of Coal Science & Technology 2020年第4期7卷 652-661页

作者： Xiaojing Yang daniel Kozar daniel gorski Anthony Marchese James Pagnotti Rusty Sutterlin Mohammad Rezaee Mark S.Klima Sarma V.Pisupati John and Willie Leone Family Department of Energy and Mineral Engineering and the EMS Energy Institute Center for Critical MineralsThe Pennsylvania State University110 Hosier BuildingUniversity ParkPA 16802USA Texas Mineral Resources Corporation.539 El Paso St Sierra BlancaTX 79851USA Pagnotti Enterprises 46 Public SquareWilkes-BarrePA 18701USA Inventure Renewables Inc161625th Avenue.TuscaloosaAL 35401USA

This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive *** than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY *** samples from each site were analyzed by ICP-MS to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and *** Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash ***,ash content has been widely used as an indicator of high REY *** may not be applicable for a specific *** B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more *** demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable *** demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP *** is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-MS/OES.

关键词： Rare earth elements XRF analysis Correlations Prediction ICP analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

XRF Standardless Comparison of Mining Head and Tail Grades to Screen and Display Ore Processing Recoveries

引用

American Journal of Analytical Chemistry 2016年第11期7卷 785-796页

作者： Nicholas E. Pingitore Jr Juan W. Clague daniel gorski Department of Geological Sciences The University of Texas at El Paso El Paso Texas USA Environmental Engineering & Public Health LLC El Paso Texas USA Texas Mineral Resources Corporation Sierra Blanca Texas USA

Separation of target elements or minerals from their host rock or ore is essential to successful mining operation. The inevitable loss of a portion of the desired material that accompanies each step in the extraction process must be documented to develop the operational protocol. Superposition of the characteristic X-ray fluorescence spectra of head (crushed rock ore particles, pre-processing) and tail (post-processing particles) samples provides a direct visual comparison of relative peak sizes, and thereby the relative concentrations, of elements of interest. If the head and tail peaks are identical, none of the element was recovered in the extraction process. At the other extreme if the tail peak “flat lines”, i.e., there is no peak, there was 100% recovery of that element. Standardless visual comparison is valid if the same mass of identical starting material is incorporated into the head and tail sample analysis pucks, and XRF analytical conditions are identical. The considerable time and expense of acquiring and calibrating the standards associated with XRF analysis of 75 or more elements are avoided, a significant advantage during initial broad screening of an experimental extraction procedure. Full quantitation by XRF or an alternate technique can proceed at a later project stage, if desired. The approach retains and presents all features of the original data, thus eliminating questions about data quality, standards and their calibration, and data manipulation in processing from raw counts to concentrations in printout tables. This form of display is ideal for both the mining professional and such less technical groups as corporate staff, investors, regulators, and the public. Examples presented herein are for heap leaching;the protocol can be applied as well to any of the other traditional ore processing and beneficiation procedures, e.g., gravity concentration, magnetic and electrical separation, froth flotation, and ore sorting.

关键词： XRF (X-Ray Fluorescence) Ore Processing Heap Leach Standardless Analysis Round Top Mountain Rare Earth Elements

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Remarkably Consistent Rare Earth Element Grades at Round Top Yttrofluorite Deposit

引用

Advances in Materials Physics and Chemistry 2018年第1期8卷 1-14页

作者： Nicholas E. Pingitore Jr. Juan W. Clague daniel gorski Department of Geological Sciences The University of Texas at El Paso El Paso TX USA Environmental Engineering & Public Health LLC El Paso TX USA Texas Mineral Resources Corporation Sierra Blanca TX USA

The peraluminous rhyolite that forms Round Top Mountain (approximately 375 m high × nearly 2 km in diameter), near Sierra Blanca, Hudspeth County, west Texas, USA, is enriched in yttrium and heavy rare earth elements (YHREEs), as well as Li, Be, U, Th, Sn, F, Rb, Cs, Nb, and Ta. Texas Mineral Resources Corp. (USA) proposes to release the YHREEs from their unique yttrofluorite host via heap leaching with dilute sulfuric acid. The inexpensive process also releases portions of valuable byproduct Be, Li, and U from accessory minerals amid the insoluble feldspars and quartz that comprise 90% - 95% of the surface-exposed rhyolite mountain. The objective of this study is to determine the consistency of mineralization grade, an important consideration in mine planning and preliminary economic analysis. The method is to plot elemental analyses of Y, Dy, Ho, Tm, Yb, Ce, Pr, Nd, Eu, Gd, Tb, U, and Nb from more than 1400 reverse circulation cuttings taken from 64 exploration drill holes against sample depth. The result of inspection of the plots reveals a remarkably homogeneous distribution of minor and trace elements throughout the sampled portion of the massive, 1.6-billion-tonne laccolith. The plots drive the conclusion that Round Top mine feedstock should remain constant for the life of the mine (multiple decades). Thus mining mechanics could be optimized at the start of operations and not require expensive later changes. The physical and chemical design of the heap leach and recovery and purification of target elements from pregnant leach solution also could be perfected during early development.

关键词： Heavy Rare Earth Elements Deposit Grade Round Top Mountain Heap Leach Mineral Processing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microprobe Mapping of Rare Earth Element Distribution in Round Top Yttrofluorite Deposit

引用

Advances in Materials Physics and Chemistry 2018年第1期8卷 15-31页

作者： Nicholas E. Pingitore Jr. Margaret Piranian Lorraine M. Negron daniel gorski Department of Geological Sciences The University of Texas at El Paso El Paso TX USA Texas Mineral Resources Corporation Sierra Blanca TX USA

The electron microprobe maps the spatial distribution of elements in a rock at a sub-mineral-grain scale to provide a basis for understanding mineralization processes and to determine optimal strategies for extraction of valuable target elements. Round Top Mountain (near the town of Sierra Blanca, Hudspeth County, west Texas, USA) is a peraluminous rhyolite laccolith that is homogeneously mineralized at over 500 ppm rare earths, more than 70% of which are yttrium and heavy rare earths (YHREEs). The massive deposit is exposed at the surface as a mountain some 2 km in diameter and 375 m in height. Round Top Mountain also contains Li, Be, U, Th, Nb, Ta, Ga, Rb, Cs, Sn, and F. The valuable YHREEs are hosted in yttrofluorite, which is soluble in dilute sulfuric acid. Texas Mineral Resources Corporation proposes to surface mine, crush, and heap leach the deposit. The distribution of YHREEs, and that of other trace elements, is remarkably homogeneous at outcrop drill hole scale. Here we document that YHREE mineralization appears pervasive through the rhyolite at a millimeter scale. Back scattered electron (BSE) and characteristic X-ray maps reveal the fine grain size and apparently random and dispersed spatial distribution of the yttrofluorite that hosts Round Top’s valuable YHREEs. The yttrofluorite grains do not appear to cluster at special mineralized locations, e.g., in pores or along cracks in the rhyolite. The same is apparently true of such other potentially valuable minerals as cassiterite and uranium species. These findings confirm that the distribution of YHREEs in Round Top Mountain rhyolite is homogeneous through different orders of magnitude of scale, i.e., from outcrop (as seen in the companion work in this volume) to sub-thin section. The material thus is ideal for a heap leach operation where homogeneous feedstock is crucial to consistent and economic operation. The findings also confirm and explain why mechanical separation would prove very difficult and e

关键词： Heavy Rare Earth Elements Yttrofluorite Electron Microprobe Micromapping Round Top

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

ArcGIS<sup>TM</sup>and Principal Component Analysis of Probe Data to Micro-Map Minerals in Round Top Rare Earth Deposit

引用

Advances in Materials Physics and Chemistry 2020年第2期10卷 39-52页

作者： Lorraine M. Negrón Margaret Piranian Maria A. Amaya daniel gorski Nicholas E. Pingitore Department of Geological Sciences The University of Texas at El Paso El Paso TX USA School of Nursing The University of Texas at El Paso El Paso TX USA Texas Mineral Resources Corporation Sierra Blanca TX USA

Rare earth elements (REEs), especially heavy rare earth elements (HREEs), are in demand for their current and emerging applications in advanced technologies. Here we perform computer-driven micro-mapping at the millimeter scale of the minerals that comprise Round Top Mountain, in west Texas, USA. This large rhyolite deposit is enriched in HREEs and such other critical elements as Li, Be, and U. Electron probe microanalysis of 2 × 2 mm areas of thin sections of the rhyolite produced individual maps of 16 elements. These were superimposed to generate a 16-element composition at each pixel. Principal components analysis of elements at each pixel identified the specific mineral at that site. The pixels were then relabeled as the appropriate minerals, thereby producing a single mineral map. The overall mineral composition of the 7 studied samples compared favorably with prior analyses of the Round Top deposit available in the literature. Likewise the range of porosity in the maps was consistent with that of previous direct measurements by water saturation. This new statistical and GIS-based technique provides a robust and unbiased approach to electron microprobe mapping. The study further showed that the high-value yttrofluorite grains exhibited little tendency to cluster with other late-stage trace minerals and that the samples extended the previously documented overall homogeneity of the deposit at field scale to this microscopic scale.

关键词： ArcGISTM Electron Probe Microanalysis Principal Component Analy-sis Rare Earths Yttrofluorite X-Ray Map Analyzer Round Top

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

ArcGIS<sup>TM</sup>Proximity and Cluster Analysis of Electron Probe Micro-Maps of Round Top Critical Mineral Deposit

引用

Advances in Materials Physics and Chemistry 2020年第3期10卷 63-76页

作者： Lorraine M. Negrón Margaret Piranian Maria A. Amaya daniel gorski Nicholas E. Pingitore Department of Geological Sciences The University of Texas at El Paso El Paso Texas USA School of Nursing The University of Texas at El Paso El Paso Texas USA Texas Mineral Resources Corporation Sierra Blanca Texas USA

Critical and rare earth elements are in high demand for their increasing incorporation in modern technological devices for applications in the military, industrial, commercial, and consumer sectors. Round Top Mountain, a rhyolite laccolith in Sierra Blanca, west Texas, U.S.A. is a unique mineral deposit that offers opportunity for development of rare earth elements, especially the heavy rare earths, as well as associated critical elements. The main objective here is to evaluate the distances between accessory minerals of potential economic value (yttrofluorite, cryolite, uraninite, thorite, cassiterite, and columbite), and to major (potassium feldspar, albite, and quartz) and minor minerals (annite mi-ca, magnetite, and zircon). In this study we explore the proximity and clustering of these minor and accessory minerals, at the mi-cron-to-millimeter scale, from mineral maps constructed in a previous application of ArcGISTM tools to electron probe microanal-ysis (EPMA) element maps. Our goal is to determine whether specific minerals cluster spatially and, if so, at what distances. We noted that the high-value target yttrofluorite grains often neighbor potassium feldspar and quartz grains, but less commonly magnetite and mica grains. With regard to cluster analysis, most minor and accessory minerals were found to group together at small scales (low micrometer) and were dis-persed or random at larger (up to 1 mm) distances.

关键词： ArcGISTM EPMA Proximity Ripley’s K-Function Critical Minerals Yttro-fluorite Round Top Deposit

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：