it honestly depends on the item and jewel both
For example:
If it is a shako, I almost always prefer "green" jewel in shako
Another example:
If it is a cold facet, it should be "Blue"
If it is a fire facet, it should be "Red"
If it is a light facet, it should be "White" or "Yellow"
if it is a poison facet, it should be "green"
Also a 3rd example:
If it's going in something 4 socket or greater like shield armor or wepeon, you can use 2x different colors and try to place them in an organized pattern
So all color jewels matter my friend

Even unid jewels matter
This post was edited by elitegamertag on Jan 15 2019 01:50pm