The oldest emeralds are about 3 billion years old and, according to available records were already known and sold in the Babylonian markets in 4000 BC.
It is a cross-cultural gemstone referred to in the Book of Revelation as one of the cornerstones of the Celestial City.
The twelve apocalyptic gems are intimately related to the twelve apostles. This relationship, confirmed by the writings of Andreas, bishop of Caesarea (563-637 AD), who wrote about this precious stone: “… The green Emerald is fed with oil so that its transparency and beauty cannot change. This stone designed to signify John the Evangelist. He calmed souls struck down by sin with holy oil, and by the grace of his excellent doctrine lent constant strength to our faith ”…
Saint John the Evangelist, the Apostle John, was one of Jesus twelve disciples. He was known as the Evangelist because he wrote the Fourth Gospel and the Book of Revelation. According to Catholic theologians, the Emerald was the physical representation of loyalty, hope, truth, genuineness and authenticity.