It’ almost always an adventure. SURC’S November trip to the Mining District outside Milford, Utah was. 9 vehicles + Jeff’s 4x toy, ventured 15 miles north and then west from Minersvile to the Power Line Road.
It’s all dirt roads from there. Travel 8+ miles (just past gas pipe vent #238) and turn right. If you have a vehicle to park it’s the best place. 
You’ll travel about 4 miles (we forgot to write down the odometer reading), but based on overall mileage it’s close. When you get to the end of the graded road it forks left/right. Take the right side up the side of the mountain.
You’ll see a large number of quartz pieces and you can park there and collect. If you have a standard pickup, or smaller 4 x 4, you can continue up the road to the head of the mine. Drive slow, the track is narrow but it’s not far to the end.
Enjoy.