GregTech CEu Version

2.8.10, applies to all recent versions

Related Problem

Depending on your monitor and settings tetrahedrite veins have very poor visibiltiy against netherrack since both stibnite and tetrahedrite blend very well against it, this makes mining those veins feel a bit janky. I pretty commonly see people install ore visibility texture packs and I think tetrahedrite is the main culprit here.

I think ideally all ores should be visible on a decent monitor with highest brightness setting in minecraft and no torches without too much eye strain. Since mining is often a relaxing activity for players I think it's important that it's comfortable.

Your Solution

To fix just shift the hue and/or brightness of the tetrahedrite ore texture to improve its contrast against the base netherrack texture it will be placed onto.

Additional Information

I think maybe sheldonite veins in the end could get the same treatment as well.

Count me in the list of people who need to install ore texture packs. Tetrahedrite is in fact nearly invisible to me (and some 5% of the male population) who are at least partially red/green colorblind.