Once humans began to advance so came a new rise of stone droppers. But they were to lazy to build a completely new version so they made another dropping part beside it and increased the value a little bit.
The advanced stone dropper is the tier 2 version of the 3 tiers of stone droppers. This dropper spits out 2 ores at once every 4 seconds with a value of $10.
It can be upgraded to the Stone Quarry.