Actually, I have been working on this in the new edition of Jaiman. I will share some details.
The key is a ring, and it opens the Tomb of Andraax. But there are others. The Clergy of the Dia Khovaria (Space Master) of a certain rank all wear an 'integrated signet ring' which is a fusion of K'ta'viir and Space Master tech (wonder how that came about?), and those rings also function as Andraax keys. More to come soon.