View previous topic :: View next topic |
Author |
Message |
Tobi
Site Admin
Joined: 07 Apr 2009
Posts: 4106
Location: Germany
|
Posted: Apr 15, 2019 01:09 Post subject: Re: Don Lum Collection |
|
|
Wonderful specimens as usual, Don, both the aquamarine and the bastnäsite.
Any idea how and why these hollow (?) tubes in the aquamarine crystal develop?
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 15, 2019 11:56 Post subject: Re: Don Lum Collection |
|
|
Tobi wrote: | Wonderful specimens as usual, Don, both the aquamarine and the bastnäsite.
Any idea how and why these hollow (?) tubes in the aquamarine crystal develop? |
Tobi, I have wondered about these tubes myself but do not know how or why they form. Some of these tubes are filled with liquid. I believe some of the FMF members can enlighten us. Thanks for the great question. Sorry I don't have an answer for you.
Regards,
Don
_________________ hogwild |
|
Back to top |
|
|
Kevin Conroy
Joined: 03 Dec 2018
Posts: 78
Location: Saint Louis, Missouri
|
Posted: Apr 15, 2019 14:59 Post subject: Re: Don Lum Collection |
|
|
The following is from: Dissolution Behaviour of Beryl, vorgelegt von MSc. Geology, Raji Kurumathoor Parameshwaran, geb. in Taliparamba, Kerala, India, on page 101:
"The study of inclusions is widely used by the gemmologists to recognise natural gem stones from the synthetic ones. Because of the fluids used in the synthesis of most gems in the laboratory usually are quite unlike those present in nature (Roedder, 1982). The inclusions manifest the identifying characteristics of the pegmatitic growth process. Aquamarine is often traversed by fine growth tubes parallel to c-axis in concurrence with the structural peculiarities of beryl having hollow channels between silicate rings (Gübelin, 1953). These inclusions known as "rain" are used as a positive identification of aquamarine by gemmologists. According to Gübelin, 1953, the beryl structure causes the development of growth tubes either hollow or filled with foreign substances. "
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 15, 2019 15:44 Post subject: Re: Don Lum Collection |
|
|
Kevin Conroy wrote: | The following is from: Dissolution Behaviour of Beryl, vorgelegt von MSc. Geology, Raji Kurumathoor Parameshwaran, geb. in Taliparamba, Kerala, India, on page 101:
"The study of inclusions is widely used by the gemmologists to recognise natural gem stones from the synthetic ones. Because of the fluids used in the synthesis of most gems in the laboratory usually are quite unlike those present in nature (Roedder, 1982). The inclusions manifest the identifying characteristics of the pegmatitic growth process. Aquamarine is often traversed by fine growth tubes parallel to c-axis in concurrence with the structural peculiarities of beryl having hollow channels between silicate rings (Gübelin, 1953). These inclusions known as "rain" are used as a positive identification of aquamarine by gemmologists. According to Gübelin, 1953, the beryl structure causes the development of growth tubes either hollow or filled with foreign substances. " |
Thank you very much for your erudite explanation, Kevin.
Don
_________________ hogwild |
|
Back to top |
|
|
Tobi
Site Admin
Joined: 07 Apr 2009
Posts: 4106
Location: Germany
|
Posted: Apr 22, 2019 02:17 Post subject: Re: Don Lum Collection |
|
|
Yes, thanks Kevin!
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 24, 2019 20:36 Post subject: Re: Don Lum Collection |
|
|
In Memory of Heimo Hellwig
Mineral: | Azurite, Cerussite |
Locality: | Tsumeb Mine, Easter Pocket, Tsumeb, Otjikoto Region, Namibia | |
|
Dimensions: | 35 mm x 22 mm x 22 mm |
Description: |
ex Georg Gebhard Lustrous dark blue twinned Azurite with Cerussite. |
|
Viewed: |
12397 Time(s) |
|
Mineral: | Azurite, Cerussite |
Locality: | Tsumeb Mine, Easter Pocket, Tsumeb, Otjikoto Region, Namibia | |
|
Dimensions: | 35 mm x 22 mm x 22 mm |
Description: |
ex Georg Gebhard Broad flat blade of Azurite. |
|
Viewed: |
12390 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 25, 2019 15:22 Post subject: Re: Don Lum Collection |
|
|
Quartz with phantoms
Mineral: | Quartz (variety amethyst, variety smoky quartz) |
Locality: | Goboboseb Mountains, Brandberg area, Erongo Region, Namibia | |
|
Dimensions: | 92 mm x 37 mm |
Description: |
Quartz crystal with phantoms |
|
Viewed: |
12343 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
jose luis jara jara
Joined: 18 Apr 2019
Posts: 114
Location: Fuenlabrada
|
Posted: Apr 25, 2019 15:27 Post subject: Re: Don Lum Collection |
|
|
I like the ghost of amethyst in quartz
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 25, 2019 15:38 Post subject: Re: Don Lum Collection |
|
|
jose luis jara jara wrote: | I like the ghost of amethyst in quartz |
Thank you for pointing him/her out, Jose.
_________________ hogwild |
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: Apr 30, 2019 20:02 Post subject: Re: Don Lum Collection |
|
|
Elmwood
Mineral: | Calcite, Barite, Micro Fluorite |
Locality: | Elmwood Mine, Carthage, Central Tennessee Ba-F-Pb-Zn District, Smith County, Tennessee, USA | |
|
Dimensions: | 195 mm x 190 mm x 130 mm |
Description: |
|
Viewed: |
12194 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 01, 2019 12:24 Post subject: Re: Don Lum Collection |
|
|
Nigeria
Mineral: | Schorl (Tourmaline Group), Muscovite |
Locality: | Ofiki, Oyo State, Nigeria | |
|
Dimensions: | 29 cm x 25 cm x 22.5 cm |
Description: |
|
Viewed: |
12151 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 01, 2019 22:28 Post subject: Re: Don Lum Collection |
|
|
Oppu Mine
Mineral: | Rhodochrosite after Calcite |
Locality: | Oppu Mine, Nishimeya-mura, Nakatsugaru District, Aomori Prefecture, Tohoku Region, Honshu Island, Japan | |
|
Dimensions: | 12 cm x 6.1 cm x 3.4 cm |
Description: |
|
Viewed: |
12132 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
Tobi
Site Admin
Joined: 07 Apr 2009
Posts: 4106
Location: Germany
|
Posted: May 02, 2019 02:04 Post subject: Re: Don Lum Collection |
|
|
After seeing the recent specimens, I think this topic should be re-named, instead of Don Lum Collection it should be DON LUM MINERAL MUSEUM!
I'm in awe, Don, they're getting better and better! :-)
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 02, 2019 11:54 Post subject: Re: Don Lum Collection |
|
|
Tobi wrote: | After seeing the recent specimens, I think this topic should be re-named, instead of Don Lum Collection it should be DON LUM MINERAL MUSEUM!
I'm in awe, Don, they're getting better and better! :-) |
Tobi, I am humbled by your comment and glad you are enjoying the collection. I appreciate your taking the time to write.
Sincerely,
Don
_________________ hogwild |
|
Back to top |
|
|
Kevin Conroy
Joined: 03 Dec 2018
Posts: 78
Location: Saint Louis, Missouri
|
Posted: May 02, 2019 13:50 Post subject: Re: Don Lum Collection |
|
|
Don, awesome pseudomorph!
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 02, 2019 15:04 Post subject: Re: Don Lum Collection |
|
|
Kevin Conroy wrote: | Don, awesome pseudomorph! |
Thank you, Kevin. I appreciate your comment.
Regards,
Don
_________________ hogwild |
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 02, 2019 15:40 Post subject: Re: Don Lum Collection |
|
|
Rhodochrosite
The label reads Rhodochrosite after Baryte, Oppu Mine. I think that this is Rhodochrosite after perhaps Tetrahedrite or Chalcopyrite or Sphalerite.
I would appreciate any opinion about what the mineral was that was replaced by the Rhodochrosite in this specimen.
Thank you.
Mineral: | Rhodochrosite |
Locality: | Oppu Mine, Nishimeya-mura, Nakatsugaru District, Aomori Prefecture, Tohoku Region, Honshu Island, Japan | |
|
Dimensions: | 15.2 cm x 11.7 cm x 4.7 cm |
Description: |
|
Viewed: |
11978 Time(s) |
|
Mineral: | Rhodochrosite |
Locality: | Oppu Mine, Nishimeya-mura, Nakatsugaru District, Aomori Prefecture, Tohoku Region, Honshu Island, Japan | |
|
Dimensions: | 15.2 cm x 11.7 cm x 4.7 cm |
Description: |
|
Viewed: |
11973 Time(s) |
|
_________________ hogwild |
|
Back to top |
|
|
Tobi
Site Admin
Joined: 07 Apr 2009
Posts: 4106
Location: Germany
|
Posted: May 07, 2019 12:59 Post subject: Re: Don Lum Collection |
|
|
Don Lum wrote: | Rhodochrosite Pseudomorph
The label reads Rhodochrosite after Baryte, Oppu Mine. I think that this is Rhodochrosite after perhaps Tetrahedrite or Chalcopyrite or Sphalerite.
I would appreciate any opinion about what the mineral was that was replaced by the Rhodochrosite in this specimen.
Thank you. | An interesting specimen Don, but I have no idea on this. The only pseudomorphs of rhodochrosite that I know from Oppu Mine are after calcite. Maybe this is a strange kind of it but it does not look like it once was calcite ... or barite ...
I hope that one of us can solve this riddle!
|
|
Back to top |
|
|
Don Lum
Joined: 03 Sep 2012
Posts: 2856
Location: Arkansas
|
Posted: May 07, 2019 13:46 Post subject: Re: Don Lum Collection |
|
|
Thank you, Tobi.
_________________ hogwild |
|
Back to top |
|
|
Bob Morgan
Joined: 18 Jan 2018
Posts: 228
Location: Savannah, Georgia
|
Posted: May 07, 2019 16:23 Post subject: Re: Don Lum Collection |
|
|
Looking through pics on mindat there are coatings of quartz and calcite. Yours looks like neither. The calcite coatings are of scalenahedral shaped crystals. Yours looks like simple rhombs.
Since both calcite and rhodochrosite are rhombohedral, I wouldn't rule out this simply being a rhodochrosite specimen.
It appears that the Oppu Mine produced both botryoidal and rather sharp crystals. Perhaps this is botryoidal overcoating of a prior generation of rhombs or three way blades.
'Just speculating. There's nothing really like yours on Mindat.
|
|
Back to top |
|
|
|