Mirror of Khoronz

Many years have passed since you went on the quest for the Talisman of Khoronz, a journey which led beyond the confines of your own space and time to the enchanted isle of Karos.
The adventure was fraught with many dangers, but there was at last the satisfaction of an intricate problem solved and a treasure won.
In your study are numerous mementoes of that quest - first the Talisman itself, an article which unaccountably lost its power when brought into your own world.
Next the finely-wrought things of gold, silver and precious stones and the many unmounted gems. They are not the sort of thing which is easily turned into money - too many questions would be asked – so you have always kept their existence a secret from all but a few close friends.
Rising from your desk, you cross the room to gaze at the most enigmatic of all the treasures of Karos; the beautiful mirror which you found in Khoronz's lair under Mount Pykon.
It is obviously priceless, the quality of the craftsmanship and the jewels which embellish it tell you that, but is it more than it seems?
The glass is of a peculiar dark quality, throwing back a reflection which appears almost solid, so much so that you reach out your hands to grasp it.
As you touch the glass an abrupt change takes place. The surface becomes a dull grey and your reflection vanishes, to be replaced by a dense swirling mist, then you feel yourself being drawn slowly but irresistibly forward...