layers in amethyst

Just the tip of a good size piece of amethyst I received some years ago gives my entry today for

Macro Mondays: layer

 

I found myself curious enough to research this beautiful purple stone:

 

'The crystal structure of amethyst differs from that of other quartzes. It consists of an irregular superposition of alternate lamellae (layers) of right-handed and left-handed quartz.'

 

also:

'Amethyst is a violet/purple variety of quartz often used as an ornamental stone.

The name comes from the Greek words a (not) and methuskein ("to intoxicate"), referring to the belief that this gemstone protected its owner from drunkenness.'

 

Well that's OK then - but I am practically teetotal now............

Done