[ARC5] Crystals and WWII

[hwhall at compuserve.com]

> 
One of my favorites is the article that begins, "Take a block of quartz. Clamp  
it into your vise. Then get out your hacksaw...." 
>

And it had to be "good" quartz. A lot of crystal quartz is internally twinned
even when the exterior faces don't show obvious twinning. Twinned quartz 
doesn't work, apparently. The Brazilian sources around the time of the war
were producing a high percentage of untwinned crystals. There seems to be a 
good deal of mystery about natural grown crystals and how they come to be the
way they are. To me, the idea of crystal control was always somehow cool, even
if it was inconvenient.
 Wayne
WB4OGM