They may be clear.
Some of the precious stones in the foundations of the wall of New Jerusalem are common and you probably have an idea what they look like on earth. But some of the other stones are more unfamiliar. The following descriptions should help you understand their earthly appearance a little better.
1. Jasper – Jasper is opaque, dense silica mineral, showing various colors from brick red to brownish red.
2. Sapphire – Sapphire is the non-red variety of corundum (the red variety is Ruby). Sapphire is often blue but also appears as orange-pink, golden, white, and black.
3. Chalcedony – Chalcedony is finely crystallized or fibrous quartz that varies in color from pale blue, yellow, brown or gray. It has a wax like luster.
4. Emerald – Emerald is a grass-green variety of Beryl.
5. Sardonyx – Sardonyx is an onyx consisting of alternate parallel layers of sard, a deep orange-red variety of Chalcedony, and another mineral , like white Chalcedony.
6. Sardius – Sardius is an opaque orange-red or brown variety of Chalcedony.
7. Chrysolite – Chrysolite, also called Peridot, is transparent green olivine. It has a sparkling pale green color and ranges in hues from lime, yellow green, and olive green, to medium dark green.
8. Beryl – Beryl, beryllium aluminum silicate, is colorless in its pure form but ranges in colors including emerald green, blue to blue-green, yellow, greenish-gold, red, and pink. Green beryl is Emerald and blue beryl is Aquamarine. Beryl is transparent to translucent.
9. Topaz – Topaz, an aluminum fluorite silicate, is colorless, but it also occurs as yellow, blue, pink, peach, gold, green, red and brown. The light yellow, brown and pink varieties are gemstones.
10. Chrysoprasus – Chrysoprasus is a greenish-golden colored precious stone.
11. Jacinth – Jacinth is the orange variety of zircon, which is a silicate mineral. Colorless zircon is used to imitate diamonds.
12. Amethyst – Amethyst is purple transparent mineral quartz. It varies in hue from reddish purple to bluish purple.
Notably, these stones in the foundations of the wall are probably all clear. Look at Rev 21:11. The light of New Jerusalem was like a precious jasper stone, “clear as crystal.” In Rev 21:18, “the city was pure gold, like unto clear glass.” If the rest of these stones are like the jasper and the gold, they are clear.
Hope this helps,
Pastor Bevans Welder