FMF - Friends of Minerals Forum, discussion and message board

[Dennis Beals]

The La Aurora mine in Charcas, San Luis Potosi, Mexico has produced excellent pink Danburite over the years. The amount of mining being done in that mine is just a fraction of its former production due to the reserves being depleted. Other mines in Charcas produce Danburite but not the gemmy pink ,

The amount pink varies but I have seen specimens left outside that appear to have a deeper hue. Another dealer produced some very pink gem rough in a manner that he would not reveal but I assumed was with radiation.

Could they get deeper in color with exposure to sunlight such as Baryte from Taxco Guerrero or blue Topaz from Spruce Grove Colorado? Is manganese the chromophore?

Dennis

[Jordi Fabre]

Hopefully someone more expert than me can help you, but I believe that the pinkish color is not due to the managanese but to the "color centers" same as happens with the Fluorites (for example) and about the exposure to sunlight I'm afraid them will fade if you do it or at least is what the mexican people who tried to do it told to me.

Hopefully it helps...

[Pete Modreski]

A bit of an overdue added reply on this one, Dennis...
I can only agree with Jordi, that the color is most likely due to lattice defects (color centers), and it would more likely to be expected fade in sunlight, than to intensify.
Of course, minerals can be puzzling and do odd things; some blue Baryte (Stoneham CO) fades in sunlight, but some is said to intensify in color (Hartsel CO), and I don't think anyone really understands why.