In the short run, yes.
According to Bobo's Mining Level Guide (
https://www.era-go.com/forum/showthr...=1#post11079):
"Level: 99
Rocks Needed: 10150
Time per rock: 0.3 seconds
Time to level up: 50 minutes, 45.0 seconds
Time Taken: 8 weeks, 6 days, 5 hours,42 minutes, 30.0 seconds
Your total rocks: 520000"
This means you'll get 1 rock every 0.3 seconds. about 3 rocks per second, rounded up.
JakeT's Mining Guide (
https://www.era-go.com/forum/showthr...With-Pictures) ) says:
"Once you have turned all your rocks into minerals (there are 12 different minerals whose prices vary between $5-10 each) you sell them at the place to the left of Wiluna Mines.
Current Minerals
Normal Minerals:
Iron, Lead, Silver, Copper, Quartz and Gypsum ($5 each).
Rare Minerals:
Gold ($10), Diamond ($10), Emerald ($8), Ruby ($7) and Sapphire ($7)."
I haven't mined in a while but I do believe you usually get 3 minerals per rock, so in 1 second you earn around $15 per second, with the potential of ~$20, $30 if we assume gems are common.
They're also tradable so you can exchange them at the Trade Tables, unlike plain gralats from the Pizza Job. Don't get me wrong, I prefer pizza job anyway because I'd rather not mine for 8 weeks straight but I acknowledge that it is, theoretically, the best job in Era.
If I've gotten anything wrong, please tell me.