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Don Lum Collection
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Don Lum




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PostPosted: Nov 10, 2013 23:41    Post subject: Re: Don Lum Collection  

Collection specimens


1-IMG_1514.JPG
 Description:
Rhodochrosite, Manganite
Hotazel Mine, Kalahari Manganese Fields, South Africa
10.5 x 6 cm
 Viewed:  22275 Time(s)

1-IMG_1514.JPG



1-IMG_1520.JPG
 Description:
Rhodochrosite, Manganite
Hotazel Mine, Kalahari Manganese Fields, South Africa
10.5 x 6 cm
 Viewed:  22238 Time(s)

1-IMG_1520.JPG



1-IMG_1518.JPG
 Description:
Rhodochrosite, Manganite
Hotazel Mine, Kalahari Manganese Fields, South Africa
10.5 x 6 cm
 Viewed:  22289 Time(s)

1-IMG_1518.JPG



1-IMG_1543.JPG
 Description:
Hematite after Magnetite (Martite)
Payun Matru Volcano, Malargue, Mendoza, Argentina
9.5 x 3.9 x 3.7 cm
 Viewed:  22248 Time(s)

1-IMG_1543.JPG



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PostPosted: Nov 11, 2013 02:23    Post subject: Re: Don Lum Collection  

Congratulations on acquiring the rhodo from Hotazel. Even for us living in SA, that is becoming VERY difficult. I also found the hematite https://www.mineral-forum.com/message-board/files/1_img_1543_342.jpg specimen exceptional. Regards, Pierre
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PostPosted: Nov 11, 2013 11:33    Post subject: Re: Don Lum Collection  

Pierre Joubert wrote:
Congratulations on acquiring the rhodo from Hotazel. Even for us living in SA, that is becoming VERY difficult. I also found the hematite https://www.mineral-forum.com/message-board/files/1_img_1543_342.jpg specimen exceptional. Regards, Pierre


Thank you, Pierre. I am fortunate to have both of these pieces. Hello to Riana.

Sincerely,

Don

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PostPosted: Nov 11, 2013 12:08    Post subject: Re: Don Lum Collection  

Don Lum wrote:
Pierre Joubert wrote:
Congratulations on acquiring the rhodo from Hotazel. Even for us living in SA, that is becoming VERY difficult. I also found the hematite https://www.mineral-forum.com/message-board/files/1_img_1543_342.jpg specimen exceptional. Regards, Pierre


Thank you, Pierre. I am fortunate to have both of these pieces. Hello to Riana.

Sincerely,

Don



Thank you Don:-)

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PostPosted: Nov 11, 2013 22:33    Post subject: Re: Don Lum Collection  

Collection specimens


1-IMG_1567.JPG
 Description:
Hematite, Quartz
Rio Marina, Isola d'Elba, Italy
3.3 x 2.7 x 2 cm
 Viewed:  22138 Time(s)

1-IMG_1567.JPG



1-IMG_1573.JPG
 Description:
Hematite, Quartz
Rio Marina, Isola d'Elba, Italy
3.3 x 2.7 x 2 cm
 Viewed:  22145 Time(s)

1-IMG_1573.JPG



1-IMG_1575.JPG
 Description:
Baryte with inclusions
18 Mine, Paleokamariza Mines, Lavrion, Attiki, Greece
6.4 x 4.8 x 2.4 cm
 Viewed:  22167 Time(s)

1-IMG_1575.JPG



1-IMG_1580.JPG
 Description:
Hematite
Florence Mine, Egremont, England
9 x 7.5 cm
 Viewed:  22107 Time(s)

1-IMG_1580.JPG



1-IMG_1581.JPG
 Description:
Hematite
Florence Mine, Egremont, England
9 x 7.5 cm
 Viewed:  22155 Time(s)

1-IMG_1581.JPG



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PostPosted: Nov 12, 2013 14:49    Post subject: Re: Don Lum Collection  

Arkansas Quartz

The first specimen is a Coontail Quartz.

The following is an excerpt from Rockhounding Arkansas by Mike Howard: Coontail Quartz is a local name for a particular variety of smoky quartz collected at several sites adjacent to Magnet Cove. There are alternating zones of black and milky quartz.

The Runyon Mine is located one mile north of Magnet Cove.

The second specimen is a 100% natural quartz from Saline County, Arkansas. Mike told me recently that the gray color is due to fine-grained shale inclusions.



1-IMG_1610.JPG
 Description:
Quartz (var Smoky), Novaculite
Runyon Mine, Hot Spring County, Arkansas, USA
14.2 x 11.4 x 11 cm
Coontail Quartz
 Viewed:  21954 Time(s)

1-IMG_1610.JPG



1-IMG_1611.JPG
 Description:
Quartz (var Smoky), Novaculite
Runyon Mine, Hot Spring County, Arkansas, USA
14.2 x 11.4 x 11 cm
Coontail Quartz
 Viewed:  21901 Time(s)

1-IMG_1611.JPG



1-IMG_1612.JPG
 Description:
Quartz (var Smoky), Novaculite
Runyon Mine, Hot Spring County, Arkansas, USA
14.2 x 11.4 x 11 cm
Coontail Quartz
 Viewed:  22008 Time(s)

1-IMG_1612.JPG



1-IMG_1614.JPG
 Description:
Quartz
Saline County, Arkansas, USA
12.2 x 10 cm
 Viewed:  21918 Time(s)

1-IMG_1614.JPG



1-IMG_1616.JPG
 Description:
Quartz
Saline County, Arkansas, USA
12.2 x 10 cm
 Viewed:  21913 Time(s)

1-IMG_1616.JPG



1-IMG_1617.JPG
 Description:
Quartz
Saline County, Arkansas, USA
12.2 x 10 cm
 Viewed:  21974 Time(s)

1-IMG_1617.JPG



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PostPosted: Nov 12, 2013 18:04    Post subject: Re: Don Lum Collection  

Irradiated Arkansas Quartz.

At some point in the past someone decided that medium grade milky quartz was much more attractive and salable if it was irradiated.

Mike Howard told me that the process was fairly simple. The selected specimens were packed in buckets or barrels and then they were shipped to Missouri to a company that had a strong gamma source. The container was then exposed to gamma rays for a given period of time.

The quartz must contain a trace of aluminum for the process to work. Crystals from the Coleman mine was the most often used. An attempt to change by irradiation some Jeffrey quartz failed to turn it smokey, as it has no aluminum within the lattice structure.

The artificial process is a reasonable simulation of how smokey quartz forms in nature, through the presence of radioactive gamma emitters present, either as discrete minerals or within the fluids that the crystals are forming from.



1-IMG_1619.JPG
 Description:
Quartz (irradiated)
Arkansas, USA
12.4 x 7.2 cm
Irradiated
 Viewed:  21898 Time(s)

1-IMG_1619.JPG



1-IMG_1621.JPG
 Description:
Quartz (irradiated)
Arkansas, USA
12.4 x 7.2 cm
Irradiated
 Viewed:  21912 Time(s)

1-IMG_1621.JPG



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PostPosted: Nov 14, 2013 17:02    Post subject: Re: Don Lum Collection  

Collection


1-IMG_1585.JPG
 Description:
Fluorite, Quartz
Santa Gertrudis vein, Santa Librada, Mun. de Mapimí, Durango, Mexico
7.5 x 6.5 cm
 Viewed:  21578 Time(s)

1-IMG_1585.JPG



1-IMG_1588.JPG
 Description:
Skutterudite
Bou Azzer District, Anti-Atlas Mountains, Tazenakht, Ouarzazate Province, Souss-Massa-Draa Region, Morocco
6.5 x 6.4 cm
 Viewed:  21533 Time(s)

1-IMG_1588.JPG



1-IMG_1594.JPG
 Description:
Skutterudite
Bou Azzer District, Anti-Atlas Mountains, Tazenakht, Ouarzazate Province, Souss-Massa-Draa Region, Morocco
6.5 x 6.4 cm
 Viewed:  21528 Time(s)

1-IMG_1594.JPG



1-IMG_1598.JPG
 Description:
Fluorite, Quartz
Yaogangxian Mine, Hunan, China
10 x 9 cm
 Viewed:  21523 Time(s)

1-IMG_1598.JPG



1-IMG_1602.JPG
 Description:
Fluorite, Quartz
Yaogangxian Mine, Hunan, China
10 x 9 cm
 Viewed:  21561 Time(s)

1-IMG_1602.JPG



1-IMG_1604.JPG
 Description:
Fluorite, Quartz
Yaogangxian Mine, Hunan, China
10 x 9 cm
 Viewed:  21529 Time(s)

1-IMG_1604.JPG



1-IMG_1609.JPG
 Description:
Fluorite, Quartz
Yaogangxian Mine, Hunan, China
10 x 9 cm
 Viewed:  21523 Time(s)

1-IMG_1609.JPG



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PostPosted: Nov 16, 2013 13:41    Post subject: Re: Don Lum Collection  

Light sensitive minerals


1-IMG_1624.JPG
 Description:
Proustite, Acanthite pseudomorph after Silver Wire
Uchucchuacua Mine, Oyon Province, Lima Department, Peru
6.2 x 4.3 cm
 Viewed:  21431 Time(s)

1-IMG_1624.JPG



1-IMG_1627-001.JPG
 Description:
Proustite, Acanthite pseudomorph after Silver Wire
Uchucchuacua Mine, Oyon Province, Lima Department, Peru
6.2 x 4.3 cm
 Viewed:  21442 Time(s)

1-IMG_1627-001.JPG



1-IMG_1629.JPG
 Description:
Proustite, Acanthite
Imiter Mine, Anti-Atlas Mountains, Souss-Massa-Draa, Morocco
4 x 3.3 x 2.2 cm
 Viewed:  21420 Time(s)

1-IMG_1629.JPG



1-IMG_1637.JPG
 Description:
Proustite, Galena
Harz Mountains, Lower Saxony, Germany
4.1 x 3.5 cm
ex Harvard Collection
ex Elling Collection
 Viewed:  21462 Time(s)

1-IMG_1637.JPG



1-IMG_1639.JPG
 Description:
Proustite, Galena
Harz Mountains, Lower Saxony, Germany
4.1 x 3.5 cm
ex Harvard Collection
ex Elling Collection
 Viewed:  21447 Time(s)

1-IMG_1639.JPG



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PostPosted: Nov 17, 2013 16:52    Post subject: Re: Don Lum Collection  

Light sensitive minerals


1-IMG_1641.JPG
 Description:
Cinnabar, Dolomite
Tongren Mine, Washan District, Tongren Prefecture, Guizhou Province. China
5 x 3.7 cm
 Viewed:  21360 Time(s)

1-IMG_1641.JPG



1-IMG_1646.JPG
 Description:
Cinnabar, Dolomite
Tongren Mine, Washan District, Tongren Prefecture, Guizhou Province. China
5 x 3.7 cm
 Viewed:  21390 Time(s)

1-IMG_1646.JPG



1-IMG_1647.JPG
 Description:
Pyrargyrite
San Genaro Mine, Castrovirreyna Province, Huancavelica Department, Peru
2.7 x 2.5 cm
 Viewed:  21350 Time(s)

1-IMG_1647.JPG



1-IMG_1649.JPG
 Description:
Pyrargyrite
San Genaro Mine, Castrovirreyna Province, Huancavelica Department, Peru
2.7 x 2.5 cm
 Viewed:  21384 Time(s)

1-IMG_1649.JPG



1-IMG_1654.JPG
 Description:
Pyrargyrite, Calcite
Level 630 of the San Guillermo Vein, San Luis Shaft, Fresnillo, Zacatecas, Mexico
4.7 x 4.2 cm
 Viewed:  21382 Time(s)

1-IMG_1654.JPG



1-IMG_1658.JPG
 Description:
Spodumene variety Kunzite
Pech, Kunar Province, Afghanistan
6.6 x 6.5 cm
 Viewed:  21375 Time(s)

1-IMG_1658.JPG



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PostPosted: Nov 18, 2013 14:25    Post subject: Re: Don Lum Collection  

Light sensitive minerals


1-IMG_1663.JPG
 Description:
Spodumene variey kunzite
Pech, Kunar Province, Afghanistan
6 x 4.3 cm
Kunzite floater with double termination
 Viewed:  21291 Time(s)

1-IMG_1663.JPG



1-IMG_1672.JPG
 Description:
Spodumene variey kunzite
Pech, Kunar Province, Afghanistan
6 x 4.3 cm
Kunzite floater with double termination
 Viewed:  21307 Time(s)

1-IMG_1672.JPG



1-IMG_1682.JPG
 Description:
Spodumene
Namacotche, Mutala, Mozambique
8 x 2.9 cm
 Viewed:  21334 Time(s)

1-IMG_1682.JPG



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PostPosted: Nov 18, 2013 19:02    Post subject: Re: Don Lum Collection  

Nice kunzites Don, I especially like the one from Pech, Afghanistan in your last post. How did you get the colour change I wonder - was it a different light source, different direction of the crystal, or was it the different coloured background ?

Regards, Mike
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PostPosted: Nov 18, 2013 19:19    Post subject: Re: Don Lum Collection  

Mike Wood wrote:
Nice kunzites Don, I especially like the one from Pech, Afghanistan in your last post. How did you get the colour change I wonder - was it a different light source, different direction of the crystal, or was it the different coloured background ?

Regards, Mike


Thank you, Mike.

I don't write down my settings but if my memory serves me correctly, image 1663 is with filtered quartz and Reveal(General Electric Trademark) bulbs from above to highlight the termination "peaks." Image 1672 is actually closer to the true color and is with an LED light source from behind the crystal down the c-axis. I use four and sometimes five light sources and turn one or more on at a time.

I am as far from being a professional photographer as one can be.

Also if some of my photos are out of focus, it is my fault and not the camera's as my visual acuity is not what it was six or seven decades ago.

Sincerely,

Don

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PostPosted: Nov 19, 2013 01:37    Post subject: Re: Don Lum Collection  

Don Lum wrote:
Mike Wood wrote:
Nice kunzites Don, I especially like the one from Pech, Afghanistan in your last post. How did you get the colour change I wonder - was it a different light source, different direction of the crystal, or was it the different coloured background ?

Regards, Mike


Thank you, Mike.

I don't write down my settings but if my memory serves me correctly, image 1663 is with filtered quartz and Reveal(General Electric Trademark) bulbs from above to highlight the termination "peaks." Image 1672 is actually closer to the true color and is with an LED light source from behind the crystal down the c-axis. I use four and sometimes five light sources and turn one or more on at a time.

I am as far from being a professional photographer as one can be.

Also if some of my photos are out of focus, it is my fault and not the camera's as my visual acuity is not what it was six or seven decades ago.

Sincerely,

Don


I can see your passion for specimens Don. You take a lot of time and care to make stands for all of them. Thank you for sharing your WONDERFUL hobby with us:-)

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PostPosted: Nov 19, 2013 10:40    Post subject: Re: Don Lum Collection  

Pierre Joubert wrote:
Don Lum wrote:
Mike Wood wrote:
Nice kunzites Don, I especially like the one from Pech, Afghanistan in your last post. How did you get the colour change I wonder - was it a different light source, different direction of the crystal, or was it the different coloured background ?

Regards, Mike

Thank you, Mike.

I don't write down my settings but if my memory serves me correctly, image 1663 is with filtered quartz and Reveal(General Electric Trademark) bulbs from above to highlight the termination "peaks." Image 1672 is actually closer to the true color and is with an LED light source from behind the crystal down the c-axis. I use four and sometimes five light sources and turn one or more on at a time.

I am as far from being a professional photographer as one can be.

Also if some of my photos are out of focus, it is my fault and not the camera's as my visual acuity is not what it was six or seven decades ago.

Sincerely,

Don

I can see your passion for specimens Don. You take a lot of time and care to make stands for all of them. Thank you for sharing your WONDERFUL hobby with us:-)

Thank you for your kind comment, Pierre. I do enjoy my minerals. Hi to Riana.

Regards,

Don

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PostPosted: Nov 19, 2013 16:12    Post subject: Re: Don Lum Collection  

Thank you for your reply Don. I wonder if the 'filtered quartz and reveal' bulb is an arc-light type bulb with quartz glass which would allow UV light to illuminate the subject, thus producing the strong pink colour of the kunzite in image 1663. Could it then be fluorescence causing the colour change?

Best regards, Mike
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PostPosted: Nov 19, 2013 17:14    Post subject: Re: Don Lum Collection  

Mike Wood wrote:
Thank you for your reply Don. I wonder if the 'filtered quartz and reveal' bulb is an arc-light type bulb with quartz glass which would allow UV light to illuminate the subject, thus producing the strong pink colour of the kunzite in image 1663. Could it then be fluorescence causing the colour change?

Best regards, Mike


Dear Mike,

What I used was a quartz halogen lamp that has a clear plate over the bulb (factory installed) and a Reveal GE (TM) bulb which has a "full spectrum" although I don't know the exact wavelength of the light emitted. I used a sheet of white copy paper between the light(s) and the specimen and that seemed to bring out the surface details which were washed out without the paper. I also used that technique in the last Russian Fluorite specimen that I posted a while back on FMF. I hope this helps.

Sincerely,

Don

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PostPosted: Nov 19, 2013 17:47    Post subject: Re: Don Lum Collection  

Ahhh, now I see the light ! Thanks for explaining that Don. The paper between the light and the subject technique sounds neat, I'll have to give that a go.

Sincerely yours,

Mike : )
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PostPosted: Nov 19, 2013 18:09    Post subject: Re: Don Lum Collection  

Today I am posting the last two of the light sensitive minerals that I have photographed; then back to storage to preserve what color is left for the next owner(s).

The first specimen is an Ametrine slab polished on both sides from the Anahi Mine in Bolivia. This specimen demonstrates the alternating zones of purple and yellow within these natural bi-color crystals. The purple (Amethyst) shows strong Brazil-law twinning. The yellow (Citrine) areas do not show twinning. Two separate individual colored crystals grew together to form an alternating "radiation" pattern of yellow and purple triangles when viewed down the c-axis. This material is found in only one place in the world



1-IMG_1677.JPG
 Description:
Ametrine (Slab polished on both sides)
Anahi Mine, La Gaiba District, Sandoval Province, Santa Cruz Department, Bolivia
7.2 x 6.2 x 1.8 cm
 Viewed:  21052 Time(s)

1-IMG_1677.JPG



1-IMG_1678.JPG
 Description:
Ametrine (Slab polished on both sides)
Anahi Mine, La Gaiba District, Sandoval Province, Santa Cruz Department, Bolivia
7.2 x 6.2 x 1.8 cm
 Viewed:  21083 Time(s)

1-IMG_1678.JPG



1-IMG_1685.JPG
 Description:
Realgar, Orpiment
Quiruvilla, Santiago de Chuco, La Libertad, Peru
6.6 x 5 cm
 Viewed:  21064 Time(s)

1-IMG_1685.JPG



1-IMG_1688.JPG
 Description:
Realgar, Orpiment
Quiruvilla, Santiago de Chuco, La Libertad, Peru
6.6 x 5 cm
 Viewed:  21046 Time(s)

1-IMG_1688.JPG



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PostPosted: Nov 19, 2013 19:05    Post subject: Re: Don Lum Collection  

Don Lum wrote:
Mike Wood wrote:
Thank you for your reply Don. I wonder if the 'filtered quartz and reveal' bulb is an arc-light type bulb with quartz glass which would allow UV light to illuminate the subject, thus producing the strong pink colour of the kunzite in image 1663. Could it then be fluorescence causing the colour change?

Best regards, Mike


Dear Mike,

What I used was a quartz halogen lamp that has a clear plate over the bulb (factory installed) and a Reveal GE (TM) bulb which has a "full spectrum" although I don't know the exact wavelength of the light emitted. I used a sheet of white copy paper between the light(s) and the specimen and that seemed to bring out the surface details which were washed out without the paper. I also used that technique in the last Russian Fluorite specimen that I posted a while back on FMF. I hope this helps.

Sincerely,

Don


Mike, the image I am referring to is: https://www.mineral-forum.com/message-board/files/1_img_1386_168.jpg
1-IMG_1386.JPG posted on October 18, 2013, page 15 of my collection. Fluorite from the 2nd Soviet Mine.

Don

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