Cor Lapis can be founded under cliff.
You can get about 12 Cor Lapises.
You can get about 10 Cor Lapises.
Mt. Hulao is the best location to farm Cor Lapis. You can find them near the teleport point.
Puzzles, Secrets, and Hidden Chests in Dragonspine
Puzzles, Secrets, and Hidden Chests in Liyue
Staff of Homa