登录注册
Quick Links : Mindat手册The Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
主页关于 MindatMindat手册Mindat的历史版权Who We Are联系我们于 Mindat.org刊登广告
捐赠给 MindatCorporate Sponsorship赞助板页已赞助的板页在 Mindat刊登 广告的广告商于 Mindat.org刊登广告
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic Time
搜索矿物的性质搜索矿物的化学Advanced Locality Search随意显示任何一 种矿物Random Locality使用minID搜索邻近产地Search Articles搜索词汇表更多搜索选项
搜索:
矿物名称:
地区产地名称:
关键字:
 
Mindat手册添加新照片Rate Photos产区编辑报告Coordinate Completion Report添加词汇表项目
Mining Companies统计会员列表Mineral MuseumsClubs & Organizations矿物展及活动The Mindat目录表设备设置The Mineral Quiz
照片搜索Photo GalleriesSearch by Color今天最新的照片昨天最新的照片用户照片相集过去每日精选照片相集Photography

Franklin Roberts' Photo Gallery

A5T-5R0Monazite-(Ce) Ce(PO4)

01181220014950314058093.jpg
Cactus Jack pegmatite, Burnet County, Texas, USA

Dimensions: 6 cm x 4 cm x 4 cm

This 6 x 4 x 4 cm radioactive crystal assemblage of monazite-ce was found buried in the soil about 10 meters west of the Cactus Jack Pegmatite in 2008. Of the hundreds of monazite specimens collected since the pegmatite was discovered in 2005, about 80% have been recovered from the soil where they ended up after being eroded from the pegmatite. Sensitive gamma scintillation counters can easily detect buried monazite specimens such as this one at depths of up to a meter. This specimen is currently in the collection of Ed Gage, of Bandera, Texas.
Copyright: © 2008, Franklin W. Roberts      Photo ID: 430689     Uploaded by: Franklin Roberts   Upload date: 2011-12-13   View Count: 323    Status: Public galleries    Type: Photo - 1721×1264 (2.2 Mpix)

12V-UEYFluorite CaF2

04757930014946728341116.jpg
Katemcy area, Mason County, Texas, USA

Dimensions: 10 cm x 7 cm x 7 cm

10cm x 7cm x 7cm nodule of massive emerald green fluorite from the Katemcy Batholith in Mason County, Texas. The specimen is back-lit to show its true color. This locality is a former topaz mine situated on a private ranch about 3 miles (5km) southeast of Katemcy, northeast of Mason. Ironically, this beautiful fluorite was considered as gangue by the miners and as such is found in abundance throughout the numerous tailings around the pit. Some of the fluorite masses uncovered are the size of soccer balls.

This green fluorite exhibits truly bizarre thermoluminescence. When strongly heated, it will begin to luminesce a bright white, which quickly shifts to canary yellow and then to a pleasing peach color. Over several minutes, the color will take on a reddish hue that will fade until the glow becomes dark magenta. Just before it appears to be fading to darkness, the familiar blue-green glow of chlorophane fluorite will again illuminate the specimen. This glow will then fade slowly until the fluorite is again dark. Unlike true chlorophane, when this fluorite has cooled, the beautiful green color will have been preserved without fading. Sunlight does not fade this material.

Mindat.org Photo of the Day - 7th May 2013
Copyright: © 2010, Franklin W. Roberts      Photo ID: 329611     Uploaded by: Franklin Roberts   Upload date: 2010-08-24   View Count: 3390    Status: Public galleries    Type: Photo - 2256×1496 (3.4 Mpix)

N8Y-LHPBeryl (Var: Aquamarine) Be3Al2Si6O18

01207960014949854186995.jpg
Cactus Jack pegmatite, Burnet County, Texas, USA

Dimensions: 5 cm x 3 cm x 3 cm

5cm x 3cm x 3cm, 100 gram aquamarine fragment discovered in blast debris while opening a cavity in the milky quartz core of the pegmatite. This was one of two large aquamarine fragments uncovered by the shot. The other fragment may be viewed here: http://www.mindat.org/photo-329446.html
Copyright: © 2010, Franklin W. Roberts      Photo ID: 329447     Uploaded by: Franklin Roberts   Upload date: 2010-08-24   View Count: 842    Status: Public galleries    Type: Photo - 1504×1000 (1.5 Mpix)

XWW-Y7GBeryl (Var: Aquamarine) Be3Al2Si6O18

09489570014950314056106.jpg
Cactus Jack pegmatite, Burnet County, Texas, USA

Dimensions: 5 cm x 5 cm x 3 cm

5cm x 5cm x 3cm semi-hexagonal crystal fragment of beryl, var aquamarine, as found, in the debris of a small blast in the quartz dike at the center of the pegmatite. The blast was intended to open up a long central cavity that was discovered at a depth of 60cm while drilling the milky quartz. The cavity was later found to extend continuously for at least 20 meters through the center of the dike. A tiny color video camera and light source was lowered into a drill hole, revealing dozens of reflective crystal faces beyond the illumination zone of the small light source. A fair proportion of these reflections were green, possibly indicating the presence of gemmy aquamarine lining the walls of the cavity. A second piece of aquamarine, a fractured 100 gram blue-green specimen, was also discovered in the debris. It may be viewed here: http://www.mindat.org/photo-329447.html
Copyright: © 2010, Franklin W. Roberts      Photo ID: 329446     Uploaded by: Franklin Roberts   Upload date: 2010-08-24   View Count: 1057    Status: Public galleries    Type: Photo - 2256×1496 (3.4 Mpix)

Mine dump at former hoist shaft

06448300014947082076210.jpg
Pavitte Copper prospect, Burnet County, Texas, USA

This is one of several dump piles located around the capped hoist shaft of the White Eagle copper/silver mine. Many colorful copper minerals can be found throughout the spoil material with a minimum of effort. Metal detectors can uncover native copper and magnetite specimens from the piles as well.
Copyright: © 2010, Franklin W. Roberts      Photo ID: 329445     Uploaded by: Franklin Roberts   Upload date: 2010-08-24   View Count: 1148    Status: Public galleries    Type: Photo - 2256×1496 (3.4 Mpix)

7JV-9XUAzurite Cu3(CO3)2(OH)2 , Malachite Cu2(CO3)(OH)2 , Fluorite CaF2

05725260014949849843545.jpg
Pavitte Copper prospect, Burnet County, Texas, USA

Dimensions: 8 cm x 6 cm x 4 cm

8cm x 6cm x 4cm specimen of Azurite and malachite on tan fluorite, self-collected from the dump at the White Eagle copper/silver mine in Burnet County, Texas.
Copyright: © 2010, Franklin W. Roberts      Photo ID: 329443     Uploaded by: Franklin Roberts   Upload date: 2010-08-23   View Count: 532    Status: Public galleries    Type: Photo - 2256×1496 (3.4 Mpix)

XHQ-9NYMolybdenite MoS2 , Microcline K(AlSi3O8)

03430680014950314064136.jpg
Petrick pegmatite, Kingsland Granite Company Quarry, Llano County, Texas, USA

This 4cm x 3cm foliated cluster of molybdenite was collected from a freshly shattered boulder of microcline that was winched from beneath 1 meter of water in the Petrick Granite quarry. The boulder was obviously rejected as dimension stone due to its "contamination" with molybdenite, fluorite and rare-earth minerals. It was dropped into the water sometime in the early 1940's and remained there until I discovered it during a dry period in 2007. By the time I had the equipment to haul it out of the pit in 2008, heavy rains had again inundated the boulder. As you can see, it was well worth the wait. The molybdenite has a mirror bright metallic luster with a pronounced blue cast. Several dozen equally impressive moly specimens were recovered from that rock.

Other minerals recovered from the boulder include gadolinite-Y, fergusonite-Y, yttrialite, powellite, uraninite and brownish-lavender fluorite, var. chlorophane.
Copyright: © 2006, Franklin W. Roberts      Photo ID: 289164     Uploaded by: Franklin Roberts   Upload date: 2010-02-24   View Count: 786    Status: Public galleries    Type: Photo - 479×434 (0.2 Mpix)

Coal Creek Serpentine (Big Branch) Prospect

04710340014947324278509.jpg
Coal Creek Serpentinite, Gillespie County, Texas, USA

The Coal Creek Serpentine Prospect in Gillespie County, Texas as photographed looking northeast from the Willow City Loop. This occurrence represents the oldest rock unit in the state of Texas. Much of the serpentinite at this location is paramagnetic, probably due to inclusions of nickel and/or chromium. Native metallic inclusions can easily be seen with a 10X loupe.

This photo was taken in April of 2008. The bluish-green serpentine contrasts sharply with the pink precambrian granites and gneisses that surround it, even when seen from space. When viewed using Google Earth (30°28'46.12"N, 98°37'51.33"W), the color contrast is striking.
Copyright: © 2009, Franklin W. Roberts      Photo ID: 223884     Uploaded by: Franklin Roberts   Upload date: 2009-04-08   View Count: 2351    Status: Public galleries    Type: Photo - 1504×1000 (1.5 Mpix)

Yttrialite "asterism"

04766390017055912292236.jpg
Petrick pegmatite, Kingsland Granite Company Quarry, Llano County, Texas, USA

Dimensions: 1 cm x 3 cm x 6 cm

Cross section of a pegmatite boulder that was found to contain a pod of yttrialite in the form of an asterism (right of center). An asterism is a nodule of rare-earth mineral, in this case yttrialite, that is surrounded by a radial fracture pattern due to stresses induced by differences in the coefficients of thermal expansion between the pod and surrounding microcline matrix. As the pegmatite cooled, the microcline contracted around the incompressible yttrialite nucleus until enormous stress fractured the microcline. I am pointing to a 1x3x6 cm crystal of gadolinite sandwiched between two plates of biotite. The dark violet inclusions above the asterism are the "puce" variety of chlorophane fluorite initially discovered one mile to the north, at Baringer Hill, by William Hidden in 1905. This fluorite was found to glow softly in the dark at room temperature with no external excitation.
Copyright: © 2009, Franklin W. Roberts      Photo ID: 223883     Uploaded by: Franklin Roberts   Upload date: 2009-04-08   View Count: 2061    Status: Public galleries    Type: Photo - 1504×1000 (1.5 Mpix)

1UW-V1RK Feldspar (Var: Adularia) KAlSi3O8 , Microcline K(AlSi3O8) , Quartz (Var: Milky Quartz) SiO2 , Biotite K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 , Gadolinite

05013740014948864095974.jpg
Petrick pegmatite, Kingsland Granite Company Quarry, Llano County, Texas, USA

Freshly exposed 2 cm specimen of adularia exhibiting its characteristic blue schiller. A small group of 5-8 mm gadolinite crystals can be seen in the lower right.
Copyright: © 2009, Franklin W. Roberts      Photo ID: 223808     Uploaded by: Franklin Roberts   Upload date: 2009-04-08   View Count: 1072    Status: Public galleries    Type: Photo - 2256×1496 (3.4 Mpix)
Page 1 of 3 (1 to 10 of 28 total)
1 2 3
 
矿物 and/or 产地  
Mindat Discussions Facebook Logo Instagram Logo Discord Logo
版权所有© mindat.org1993年至2024年,除了规定的地方。 Mindat.org全赖于全球数千个以上成员和支持者们的参与。
隐私政策 - 条款和条款细则 - 联络我们 - Report a bug/vulnerability Current server date and time: 2024.4.24 12:00:55
Go to top of page