FMF - Friends of Minerals Forum, discussion and message board

[Idahorocks]

Is it true, as I have been hearing. That all Citrine from Brazil is heated Amethyst in order to get the yellow color? And that the only true Citrine, One is able to find, is from the Congo?

Darlene

[Tobi]

It is true that the mass material which is sold as citrine from Brazil indeed is heated amethyst. These specimens have a orange or dark-brownish color, while natural citrine is much brighter and has a more pale yellow colour.

This would be a typical "citrine" made of heated amethyst:
https://www.mindat.org/photo-186265.html

while this is a typical sample of natural citrine:
https://www.mindat.org/photo-173523.html

But it is not true that "real" citrines only come from the Congo. There are also good ones (though they are really a rare quartz variety) from Brazil, or also from Russia (e.g. Dal'Negorsk) or other African countries but the Congo.

Cheers!

[John S. White]

Natural citrines also come from Charcas, Mexico, I have one. I believe they are also found in Madagascar.

[Jordi Fabre]

And in Spain...

[Amir Akhavan]

Great, Jordi, I've heard of Spanish citrines but never saw one. Nice!
More yellow than I thought for sure.

There are many citrine localities.
Good ones come from Norway, for example, deep yellow or yellow green crystals.
Or Urals and far east Siberia.
Brazilian citrine is often honey colored (but that has nothing to do with heated amethyst). The real ones look more like smoky crystals with their color being off.
Transitions to smokey quartz are common (because of the similar color centers).

I'm still not perfectly super-sure that *all* dark yellow Urals crystals are untreated.

[Luiz Menezes]

Brazil s the world largest producer of natural citrines; several tens of pegmatites, mostly in Minas Gerais state, have produced large quantities of large crystals (weighting up to several hundred kilos) with excellent color; among them I can mention the following mines: Morro Redondo (one large quartz pocket found in 1993 produced near 1 ton of high grade citrine, probably the largest and more valuable single find ever in the world), Sapo, Escondido, Pederneiras, Macaco, Pedra Alta, Cruzeiro, Campo Belo (on the 1960's), Aricanga, several mines in Coronel Murta and São Geraldo do Baixio.

The color of natural citrine can never be similar to heat-treated amethyst, the last is orange-yellow, and natural citrine can be light yellow, yellow, brownish-yellow or reddish-yellow (the more appreciated and valuable); unfortunately I don't have photos at the moment.

Luiz Menezes

[Amir Akhavan]

Hi Luiz,

One of these citrine giants was on display in the (now closed) museum "Steinzeiten" here in Hamburg. It's a 660kg crystal (660kg is twice the size of the biggest Alpine crystals) from the "Pocket de Venancio". There I've seen a documentary about its recovery from the underground pegmatite pocket, very impressive, very hard work. The specimen on display was transparent and honey-colored.
Do you know if the "Pocket de Venancio" is at Morro Redondo?

BTW, a common misconception about citrine is that they all are colored by iron impurities. That is at least not the case for the Brazilian citrines, for example, which are very low in iron. Their color center is related to aluminum impurities and irradiation. The same is probably true for the rare citrines from the Alps and those from Norway, Madagascar, Kazakhstan and the Ural Mountains.
I'm not sure about those from Lueni, Congo, and those from Aldan, Siberia.

Cheers
Amir

[Luiz Menezes]

Hi Amir:

The huge pocket at Morro Redondo (from where inside a single cavity, that after been dug measured 35 x 10 x 8 m, near 500 tons of quartz were recovered) was called "Carlau's pocket".

I will try to find out where the "Venancio pocket"was found.

Luiz

[José Miguel]

This a Citrine Quartz from Bresil.

[John S. White]

Here is an example of creating citrine by heating amethyst. One half of this geode was not heated, the other was. From Rio Grande do Sul, Brazil.

[Luiz Menezes]

Olá José Miguel:

Your nice citrine crystal looks to be from the Itinga ara, on the north of Minas Gerais; if you don't have a more specific info about the locality you can consider my suggestion.

I am annexing here photos of 2 fine citrines from São Geraldo do Baixio, Minas Gerais, from my personnal sollection.

Luiz

[Idahorocks]

All of this is such wonderful information, I shall photograph my selections of Citrine and share with you soon.
Thank you so very much for this opportunity to share.

Darlene

[José Miguel]

Thank you Luiz, I only have the info of the locality Minas Geraes for my citrine. I will include Itinga.
Now I include a citrine from Urals, Russia.
I have tryed that the color is the most accurate original color.

[Idahorocks]

Thank you John S. White that answers my question about this one today.

Darlene

[Idahorocks]

Here is one I received from Brazil. It turns out they are real Citrine from what everyone has said here.

Darlene