Five of our ten comparison Bible translations, used in this series, render the word sappiyr as "sapphire," with three others (ESV, HCSB and NIV) stating the stone could also be a lapis lazuli. The NASB translates the word directly as "lapis lazuli" while the NLT renders it "blue lapis lazuli."
Even though one of the stones that adorned Lucifer is likely a sapphire, the middle stone in the second row of the High Priest's breastplate likely is not. Please see our article on lapis lazuli for more information.
The Greek word sappheiros (Strong's #G4552) is used for the gemstone composing the second foundation in the New Jerusalem to be built by God (Revelation 21:19). All ten Bibles in this series translate sappheiros as "sapphire."
In modern times, sapphires are not only used in jewelry but also for scientific instruments, impact resistant windows and the inner workings of wristwatches.
Sapphires, in ancient times, were believed not only to be an antidote against poison but also a powerful charm that protected the wearer from fever (Diamonds, Pearls and Precious Stones, page 60).
Sapphires were thought to protect kings from harm. Those who wore the gemstone also did so because it was thought not only to protect them from envy but also to grant them favor with God. Those who were necromancers (who used black magic to trick others they were contacting the dead) highly valued this stone for its believed power to enable them to hear and understand obscure oracles (Curious Lore of Precious Stones, page 104 - 105).