just took a look at a shower that has some small decorative triangular tile insets that are spalling.  What is interesting is that only the jerusalem gold ( i believe) tiles are spalling and only along the top strip.  It is in a shower and I'm wondering what may have caused this to happen and also how to fix.  I could use epoxy perhaps to fill the deterioration, but am concerned that the epoxy will fall out along with the stone behind it (assuming that whatever is causing the stone to disintegrate keeps on happening).  I included some pictures below. 
photo j gold 1.jpgphoto j gold 3.jpgphoto j gold 2.jpgphoto j gold 4.jpg
From the desk of
Baird Standish
Managing Partner
Facility Specialists, LLC
1616 Walnut St.
Philadelphia, PA 19103
Phone: 215-732-7505
Fax: 215-546-9160