[Rockhounds] Question

[DonH]

Carolyn Reynard wrote:

> I always check  feldspars for fluorescence, most are a deep red. Under short
> wave ultra-violet light  this one is an intense light blue-white, like some
> feldspars I have from Maine and Pakistan.  No long wave response or
> phosphorescence.


Sounds about right.  I can't imagine what activates that color.  It does 
have cleavage if you break it into small pieces.  It is usually 
intergrown with other minerals like quartz and it was not easy to get a 
clean probe point.

The powder x-ray pattern for the one piece I analyzed showed it to be 
right on the border between sandine and orthoclase.

Best,
Don