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A/B axis versus C axis

I’m, sure many people have been frustrated by articles talking about A/B axis vs C Axis. I get it. So here is a simplification.
This is written regarding Tourmaline however it has other applicable uses.
Think of the C Axis being the very center of the stone extending upward. It begins at the base and extends directly to the point, through the center of the stone. The A and B are the N,S,E,W views of the stone without looking directly down the C axis. Think of it as a core, and so long as you don’t look down the core but look at it a 90 degree angles you are looking at the A/B.

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I’m going to simplify this even more. Rather than thinking of cardinal directions which is just confusing to me, consider a natural crystal that is elongated like a cylinder or in this case, like a drinking straw (but not hollow).
If you cut the pencil or straw in half (along its length) you have cut the A/B axis.
If you look along the length (or through the hole in a straw), you are looking along the C axis.