Today, we are using these same two entities of silicon and photons in optical fibers. These two are exactly the same materials that go back to the time of Abraham and later is made for the Tabernacle and the Temples in the breastplate, the Hoshen of the High Priest ( see Exodus 28: 13-30 )
The Hoshen, the breastplate of the High Priest that is the seat for communicating with the Divine. The term Urim has been traditionally been derived from the Hebrew word Or, meaning Lights. Thummim is derived from the Hebrew meaning pure, without fault. Thus the meaning of these two terms basically means –“lights and perfections” (Exodus 28:30).
This was some sort of pouch or pocket that was associated with the Hoshen- plate worn by the High priest. On the Hoshen there were twelve gemstones, each for one of the twelve tribes of the sacred community of the Israelites (Exodus 28:17).
This was used to determine a response from God to some significant question that the ruler or king of Israel needed to know about (1 Samuel 14:41).
According to the tradition the names of each of the tribes was engraved on each of the gem stones. When a question was submitted to the High Priest and in some fashion either the gems lit up in a specific sequence or the individual letters lit up to provide a response.
We can see here the association of minerals with lights that can lead to truth.
In accordance with the traditional view that Urim and Thummim should be translated as “Light and Truth”. The Latin equivalent of this phrase is “Lux et Veritas”. A significant legacy of the Hebraist who was the early president of Yale University- Ezra Stiles, has the words Urim and Tummim in Hebrew emblazoned across the open book with the Latin Lux et Veritas appears below on a banner.