[Rockhounds] unusual question

[Dennis Buffenmyer]

I must preface this question with the fact that I have very little
formal training in chemistry and geology, but greatly enjoy the hobby of
mineral collecting on many levels. Some time ago in generally discussing
minerals, and specifically zeolites, I came up with one of "my"
questions. Where did the aluminum come from? I asked. The reply was
unusual but perhaps convincing. I was told that aluminum is nearly
"ubiquitous" or everywhere. I was wondering if Potassium falls into the
same category as "ubiquitous". I would think you would need some eroded
deeper seated material to derive potassium.
Is there a metamorphic rock type that is completely devoid of aluminum
or potassium?? If in the case of stellerite, if there was NO aluminum
present to form stellerite what would it form? Or is there vacant space
where the aluminum would fit?
In the case of erionite, is it possible to be missing potassium and
still construct the same mineral??
I know aluminum is part of the framework of many minerals and potassium
does not fit into the same utilization.
Thanks for your time...
Dennis Buffenmyer