FMF - Friends of Minerals Forum, discussion and message board

[bugrock]

Hello,

Inquiring forum members to see if anyone has experience removing calcite from Ilfeld manganite specimens. I have a specimen with a number of typical thick crystal bundles on a block of solid manganite matrix. Some of the xls have calcite at their tips or in linear grooves along the sides. There is one flat mass of cleaved white calcite along the top of the xls at the center of the plate that covers up some of the xls.

Wonder if it is possible to etch the calcite off the specimen without causing damage to the manganite xls. Would use gentile technique, I like vinegar and have considerable patience with this type of task. If this is followed by liberal soaking and washing in water it has resulted in good results with other minerals. But if someone has specific experience with Ilfeld specimens I would feel more comfortable with the task. Do not want to frost the surface of the manganite xls.

In a way I am a bit reluctant to remove the center mass of calcite off the specimen as it does offer some white/black contrast. Perhaps that is why it was left as is by the collector of the piece. Just considering options.

Should point out that the matrix of this specimen is solid and black, there appears to be no danger of breaking up the plate, there is no calcite in the think black matrix of the specimen.


Thanks for your help,

George

[Jordi Fabre]

I suggest to you to take a look here -> https://www.mineral-forum.com/message-board/viewtopic.php?p=15096#15096