what were the urim and thummim, physically?

Question

various ideas abound:

http://en.wikipedia.org/wiki/Urim_and_Thummim

Answer 1

No. They were supposed to be stones for reading minds inplanted on the breastplates of Jewish Priest shirts.
Maybe?

Hugin and Munin were the two Ravens that rode on Odin"s shoulders if that is any help tp you.

Answer 2

Supposedly they were devices (like blocks or stones) used for determining the will of God. The High Priest held them in his garments, until they were needed.