Andradite

rock,this is the best i can do,,,,these came from cero de concordia,municipal de tatatila,veracruz,,,,,rock they are the best photos i can make,if i could make better ones i would go in the business,,,,ajjajaajjaja hope these help a little ab

rock,,i also wanted to thank you for you work,,thanks friend ab

Hi Rock,

For the Stanley Butte area locality in Arizona, Graham Co., San Carlos Indian Reservation - it may be worth mentioning that over the past decade, some local gem miners have developed a shallow bench cut along the deposit that has produced numerous andradite crystal clusters that contain flawless facet rough, which have cut faceted stones averaging 1.5mm in diameter, and up to 1 carat in weight. Some larger stones have also been cut, but they are exceptionally rare. Also, there have been a few "complete" crystals, or "floaters" that have been recovered from small cavities or pockets, although to date they have been few and far between the bulk of production.

Also, while definitely not the average size, I've personally seen andradite crystal covered plates from here measuring over 12 inches across, that have sold for prices well into the 4 figure range - so you're statement in the article:

"I suppose that the best specimens from here might bring two or three hundred dollars and you should be able to get a decent one for less than $50."

... Is somewhat dated, especially the value of those specimens that would qualify as "Best Minerals".

I've been prompting the local gem miners from the San Carlos Indian Reservation to join us here on mindat and add mineral photographs and site data to the database, so hopefully they will come on board one of these days. They have some exceptional mineral and locality photographs, and some great historic information as well as current affairs that would really improve the accuracy of mindat with regards to the San Carlos area.

If you need more specific size, quality, and value figures for your Best Minerals project, not to mention digital photographs - maybe you could offer them an open invitation as well - it couldn't hurt.

[www.apachegems.com]

Scott

Scott, Thats good information you have given and I will eventually get around to putting it into the article. It would be great to have the gem miners come on board and give us better pictures and more up to date information. I am reluctant to go chasing them, because I more than have my hands full trying to do what I am to get some of the other mineral species roughed in with some data and pictures in them. Almost each and every species/locality can be improved on considerably and a lot of the stuff I write about the localities, and the specimens, if there is anything at all which is more common, is many times off the top of my head, and as you pointed out, in the case of the Stanley Buttes article out of date. What I really need is about 50 guys like you to jump in add better images and write up the stuff that can go directly into the articles. Four of five guys trying to do it all is like an ant trying to eat an elephant.

Rock Currier
Crystals not pistols.

Hi Rock

You may like to consider this Andradite from Tubissis for the article.

[www.mindat.org]

Debbie,
Well, perhaps. It is a pretty nice crystal. Ill probably give it a few months to see what else may show up in the way of new images and if nothing better comes along, Ill probably stick it in.

Rock Currier
Crystals not pistols.

Here is additional information on andradites from the Oslo region.

The Oslo-region, Norway.

The Permian rift valley that fomed the present Oslo fiord with the beautiful inlet to the Norwegian capital, also resulted in one of the most interesting geological regions in Europe with diverse plutonic rocks and many localities with contact metamorphic minerals where the granites and syenites intrude Cambrosilurian sediments. Many excellent localities of andradite are known in the area which extends from the lake Mjøsa North of Oslo to Porsgrunn and Skien to the South-West. This mineral was first found by d`Andrada at the Konnerudkollen mine near Drammen and described in 1800 under the name "allochroite".

Localities in the Grua area, Hadeland, Oppland.

The largest and best crystals of andradite from Norway has been found at the locality Kalkovnen, Østhagan where sharp greenish-black crystals to more than 6 cm occur embedded in layers of calcite. The locality has been protected as a geological heritage site.
A group of andradite crystals to 5 cm embedded in calcite from Kalkovnen, Grua collected in 1968.

During tunneling for the railroad in the latter part of the 19th century a few hundred meters south of Grua station and the locality at Kalkovnen brown andradite crystals was found with large crystals of "uralite" ( actinolite pseudomorphs after diopside crystals).
Andradite crystals to 3 cm from the railroad tunnel south of Grua station collected in 1967.

Andradite is also common in the small mines and outcrops west of Grua station and especially at Skjerpemyr many pretty specimens of red andradite crystals to 5 mm on green "uralite" were collected before the mine was protected as a geological heritage site and thus off limits to collectors.
Andradite crystals to 5 mm on "uralite" from Skjerpemyr, Grua, Oppland collected in 1968.
Specimens with andradite crystals to 1-3 cm are commonly found when new roads and houses are constructed in the area.

The Drammen-area

Many small abandoned mines and other outcrops with contact metamorphic minerals can be found around the city of Drammen. Andradite is common in crystals to about 2 cm especially at the Konnerud mines, in Drammensmarka near Landfalltjern and at Lierskogen.
(The picture of the specimen from Drammen and additional information from Olav Revheim can be placed here).

Knut



Edited 3 time(s). Last edit at 10/07/2009 09:21PM by Knut Eldjarn.

Rock,
great work as usual,
maybe you could use those pictures:

[www.mindat.org]
from Canada, i will try to replace the pic with a better one asap but this find was quite recent and only few specimens available as i learned,

and

[www.mindat.org]

... and please don´t ask me about my best of articles (pseudomalachite, adding rhodos etc) .. very busy at the moment but i will be back in winter to fill the long dark evenings :-)

BTW you assigned me to the red-green mafia recently ... got a bunch of german rhodos last week and there is a nice Luise mine, Germany specimen for the article .. will try to photograph asap too,

cheers
Roger

Knut, thanks for the additions. They will eventually be incorporated into the article, but can sit comfortably in the thread till I or someone gets around to doing that.

Roger, also thanks and don't worry about your delinquent articles on mindat. Just as long as your guilty conscience keeps nagging at you I know you will eventually do what is needed. My mother taught me how to make people feel guilty.

Rock Currier
Crystals not pistols.

Rock and All-

Fantastic work on one my favorite minerals! I recently posted a few New Mexico andradites (New Mexico seems to have been overlooked!) Take a look and see what you think!

Darren in NM

Hematite on Andradite

Andradite

Andradite

Andradite

Demantoid not appreciates the light from tungsten / halogen lamp, but that of the sun or some neon. Note this incredible metamerism phenomenon on a sample of new Madagascar Demantoid (the white balance method used is the same: to left tungsten lamp, to right neon).

Both will make good additions to the article when I or someone else gets around to updating the thing.

Rock Currier
Crystals not pistols.

This is Topazolite with true colors under white light 5000k, the same for Demantoid

Mindat Page

[www.mindat.org]


Una fotografia bisogna leggerla, inutile fare mille complimenti quando questa magari ha dominanti di colore sbagliate, troppo contrasto etc... perchè già questo basta per rovinarla

Those are very nice garnet specimens. would you consider uploading them to Mindat? Could someone help me with the translation from the Italian? What is the locality of these garnets and their size?

Rock Currier
Crystals not pistols.

here all the info of the photos, for the translation the article on Rivista Mineralogica Italian its a bit long

[www.mindat.org]

Mindat Page

[www.mindat.org]


Una fotografia bisogna leggerla, inutile fare mille complimenti quando questa magari ha dominanti di colore sbagliate, troppo contrasto etc... perchè già questo basta per rovinarla