There are some good threads over at the mndat.org forum on this.

http://www.mindat.org/forum.php?read,6,5549,5549#msg-5549

http://www.mindat.org/forum.php?read,11,80084,80237#msg-80237

Bottom line? "White Buffalo Turquoise" is NOT a turquoise as we know that stone in the US. It is not a copper aluminum phosphate. It might be an alumina phosphate but it is more likely magnesite or magnesium carbonate.

Previous conversations about this asked if the so called white turquoise on the market were made from ground up stone. There are a few "carved" beads that might be made from molded, compressed powder but most of this stuff is just solid white magnesite, dyed blue (or various colors), crazed in some manner to give it good "matrix" markings and sometimes tumbled with shoe polish type materials to give solid blacks in the crevices of the "brain" or "cauliflower" style nodules.