Crushing black sands- What I've tried and a question.

FiresEye

Sr. Member
Aug 17, 2010
322
4
I've read tons of threads here about crushing black sand, but I need new advice.

So, I ran about 1/2 gallon of black sand that I know contains micro gold through a coffee grinder(dry) and it wore the stainless steel blade down FAST. I mean the blade like slowly melted away.

But then I ran that bucket through a cleanup sluice and WOW- the micro gold was amazing. Like 100+ pieces of it. Maybe like 400-500 mesh. The stuff that starts to be so small you can't see. ( sorry no pictures)




My question is, I've heard some of y'all use a cast iron mortal and pestle. Amazon sells all sorts of types. Even stainless steel ones.

I can't get a ball mill/tumbler with steel balls because it's too expensive, but some of these cast iron mortars are like $30.


Which one do you guys use? What is the cheapest way to grind black sand? I love the coffee grinder because it gets it down to dust. But the blade just wears out too fast to be cost effective.

Any help is much appreciated.
 

Upvote 0

KevinInColorado

Gold Member
Jan 9, 2012
7,037
11,369
Summit County, Colorado
Detector(s) used
Grizzly Goldtrap Explorer & Motherlode, Gold Cube with trommel or Banker on top, Angus Mackirk Expedition, Gold-n-Sand Xtream Hand pump
Primary Interest:
Prospecting
I've read tons of threads here about crushing black sand, but I need new advice.

So, I ran about 1/2 gallon of black sand that I know contains micro gold through a coffee grinder(dry) and it wore the stainless steel blade down FAST. I mean the blade like slowly melted away.

But then I ran that bucket through a cleanup sluice and WOW- the micro gold was amazing. Like 100+ pieces of it. Maybe like 400-500 mesh. The stuff that starts to be so small you can't see. ( sorry no pictures)




My question is, I've heard some of y'all use a cast iron mortal and pestle. Amazon sells all sorts of types. Even stainless steel ones.

I can't get a ball mill/tumbler with steel balls because it's too expensive, but some of these cast iron mortars are like $30.


Which one do you guys use? What is the cheapest way to grind black sand? I love the coffee grinder because it gets it down to dust. But the blade just wears out too fast to be cost effective.

Any help is much appreciated.

There’s some threads here from 5-7 years ago where we discuss bench-top rod mills in detail. I built one- works great!
 

arizau

Bronze Member
May 2, 2014
2,479
3,854
AZ
Detector(s) used
Beach High Banker, Sweep Jig, Whippet Dry Washer, Lobo ST, 1/2 width 2 tray Gold Cube, numerous pans, rocker box, and home made fluid bed and stream sluices.
Primary Interest:
Prospecting
There’s some threads here from 5-7 years ago where we discuss bench-top rod mills in detail. I built one- works great!

The thread mentioned above is titled "simple solution to fine gold recovery".
Get a set of progressively smaller screen mesh sieves and pan the batches separately...gold weighs 3 to 5 times as much as other equally sized particles so panning efforts are maximized if you pan the batches sepatately.
Any mortar pestle set should work to crush and grind.

Good luck
 

N-Lionberger

Bronze Member
Dec 1, 2013
1,359
1,950
Arcata, California
Detector(s) used
Fisher 1212-x
Fisher Gold Bug 2
Whites 4900/SP3
Dowsing rods
Primary Interest:
Prospecting
Rod mills are easy, find an old rock tumbler and use chunks of steel rod as a grinding media. The cast iron mortar and pestle I use was around the tune of 120 bucks, got it from Lunds in Mound House NV. Its about the biggest you can get. I have a small one I carry in the truck for sampling hard rock ores. Have you tried heating and quenching your sands?
 

Last edited:

Top Member Reactions

Users who are viewing this thread

Top