Betweenlands version:
3.6.0

Forge version:
1.12.2 Latest Version 14.23.5.2847

Multiplayer --> Forge Server

Installed mods:
Betweenlands 3.6.0

Description of the problem:
Gem Singer doesn't work, I am in front of a gem ore or a Life Crystal Stalactite and I use the Gem Singer and it does not show the white flash (or white wave)

can it be for some video option that I have configured?
Can anyone else test if the Gem Singer works?

How strange, my old Gem Singer has broken, and for testing I have taken a new GemSinger from the creative and ... now it works!

Dont work again, I am in front of a 2 natural gem ores

It works strangely, sometimes, having in front of a gem ore (natural generation) the Gem Singer does not detect it. Other times (somewhere else with another gem ore) if he detects it.

That's because it's random, it has always worked that way. Here's how the gem singer works in detail:
do 64 times:
pick random chunk within 6 chunk range
pick random gem type (i.e. aqua, crimson, green or life crystal)
pick random ore with that gem type
if that ore exists in chunk, mark it

Example: with a 6 chunk range there's 13x13 = 169 chunks. The chance for a single chunk with an ore to be checked with the same gem type and then be marked is 1-(1-1/169*0.25)^64 = 9%. So if you have a single ore in a superflat world expect having to use the gem singer ~10 times.
In a normal world that's not as obvious because many chunks contain at least one gem or life crystal.

I might change it to check for each gem type in each chunk and then pick a random one that exists, like that it'll find gems more reliably. Maybe it should also only use durability when it marks an ore.