>> There are those who believe that the real Stone is actually crystal or meteorite, and some
>> even believe it is associated with the Enochian Pillar.
After studying the Hill of Tara, where the stone originally stood, for a couple of years and delving deeply in the known facts about The Stone of Destiny I can honestly say I came up with nothing that would suggest any of the above other than something approximating to the crystal idea. I'd really love to see what gave anyone those ideas beyond pure imagination.
I think you have to change your tense to '<i>was</i> actually crystal or meteorite'. Although some tales tell of the stone going to Scotland, the most convincing one tells of the stone's destruction and its 'heart' 'flying' to Teltown, Co. Meath - the site of a yearly festival a few miles from Tara that ran for over 2000 years until it was stopped in the early 1800s because of the drunkenness. The church had failed to stop the event despite trying for 1000 years, but did manage to ban whiskey a few years before its demise. Everyone drank poteen instead - the outcome of which was somewhat predictable. Returning to the main subject: One of the main moves of Christianity when it reached Ireland was to try to remove power from Tara. A clear way of doing this would have been to destroy the Stone of Destiny.
In the book I'm writing about at the moment (about something almost completely different) I reveal my thoughts on what the real stone was made of in a footnote :-) My conclusion is based on three facts, a bit of juggling and a sprinkling of pure imagination.