John the Apostle
Revelation 21:19BSB·traditional attribution

The foundations of the city walls were adorned with every kind of precious stone: The first foundation was jasper, the second sapphire, the third chalcedony, the fourth emerald,

Matthew Henry Presbyterian

We have already considered the introduction to the vision of the new Jerusalem in a more general idea of the heavenly state; we now come to the vision itself, where observe, I. The person that opened the vision to the apostle - one of the seven angels, that had the seven vials full of the seven last plagues, Rev 21:9.

Commenting on Revelation 21:9-27

Jamieson-Fausset-Brown Reformed

And--so Syriac, Coptic, and ANDREAS. But A, B, and Vulgate omit. Compare Rev 21:14 with this verse; also Isa 54:11. all manner of precious stones--Contrast Rev 18:12 as to the harlot, Babylon. These precious stones constituted the "foundations." chalcedony--agate from Chalcedon: semi-opaque, sky-blue, with stripes of other colors [ALFORD].

John Gill Reformed Baptist

The fifth, sardonyx,.... Which is partly of the sardian, and partly of the onyx stone, which resembles a man's nail, from whence it has its name; it is reddish, bordering on white; it may be thought to answer to the onyx in the breastplate, on which was written the name of Joseph.