How many pounds of ore is needed for assay?

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Toddntucson7

Active member
Joined
Apr 17, 2016
Messages
37
Location
Tucson, AZ
My question is, and maybe for people just starting up, is the first step is to get a assay of your ore. Of course every expert or tradesman in the business on this forum needs to start with that to answer novice questions about "end of rainbow" dreams of gold. A lot come in the forum ask "I have X product how do I get the X valued material out?" Usually they are thinking it's as simple as using a propane torch to melt or local hardware store materials and bang their in the money. I'm goi to be a small scale miner that will be going in today to have a assay done.

I have about 200 pounds of ore, a small batch at home I collected from the site I'm about to stake claim and mine. I will probably be a collect the ore and take to refiner per truck load operation once a week maybe everyday who knows. What amount should I give the person that's going to assay? Now figure he is the one going to be buying this ore as well. Do I let him pick out ore that I know is just the host material more than the rich unsmelted parts so he will have a lower grade assay in hand so he doesn't have pay me more when I bring it back?

I have read a lot of the articles in here on sweeps and such and it seems there is a lot of trickle down economics going on out there down to refining the refiners material for that extra 1/4% of value. I want to make sure I get a proper assay done that's accurate and I want all my metals extracted back. I pay him for the work not to make a gratuity that's hidden from new comers in this. So should I say to the person doing the assay this is for, let's say selling ore on eBay giving people acrossed the world a piece of the old west lol, so I get, at least, a more accurate assay because he won't think I will be selling this ore back to him in the future?

Can a person wait until fired and sifted take a sample back for second opinion? I don't mind someone making a buck, or a percent of my work, but be upfront how much hidden things come along with it. So should I take 200 pounds in cleaned like I would normally sell or what is the minimum amount required to do an assay so the new person knows what to expect getting into this whole lovely mess we all have a love hate relationship with?

Side note' I'm doing silver as my main material, some may have gold or "X" material or does it matter do they give you a breakdown of everything in the ore?
 
Sorry that poll the poll creation popped up. I thought it took polled answers a different way as if you could write answer. My mistake now I see how to create a proper poll. Thanks, sorry....Todd
 
http://www.aallabs.com/services/fire-assay
http://prescottlab.com/assay-services

Prescott's page might help you some. Also, scavenging upper gravels doesn't always give you accurate numbers. I know of a place from personal experience that took over 20 ft deep before the numbers started reading with the per square footage.
And then there was the 2 ton boulder that was mostly silver just sitting in the creek...
 
Do we get that many polls Jim that you feel we should axe it?


Perhaps I should poll on polls.


As for the original question at hand:

Succinctly, the amount of ore needed for an assay depends on the grade of the ore. Generally 100-500 g is required for most materials. Sometimes you can get away with less, but I always ask more. Good assays should be done at least in duplicate and should not differ by much. If they do, one assay is bad, or the material is inhomogeneous right off rip and needs prepared, or BOTH.

Secondly, don't take the refiners assay unless you must and use reputable assay labs that can trace their standards back to NIST and are part of the ASTM or ISO round robin for assays on certified reference materials.

Personally, I don't provide assays on material I intend to buy unless it is all at my premises and I'm the one sampling it (don't care if customer is there or not). I may give pricing indications, a range, or a desire level of how much I'd like to process the material, but frankly, most customers expect X and get X-Y. Very rarely do they get X+Y but it does happen. Most of the time, the bias is that you have more than you really do. I do it, you do it, everyone does it. It's called hope. And of course there's sample salting, which is especially prevalent amongst miners, whose industry, again personal opinion, I find to be more crooked than refining.
 
Todd, I deleted your poll. Please don't create polls every time you have a new question.

Two moderators asked you in your last thread to break your posts into paragraphs to make them more readable. I will not waste my time trying to read a post like this, and I suspect most of our members will feel the same way.

If you want us to help, we ask that you respect our rules and our requests.

Dave
 
I am not sure why I am responding, but everyone deserves a chance.

A simple way to get a somewhat accurate assay. Close your eyes, turn around and pick up about 100 LBS of your "ore" Crush it to approx 100 mesh (100 openings to the inch). 100 lbs is approx a 20 L (5 gallon) pail of finely crushed rock. Get 10 large pill bottles. Take a sample from the crushed rock at the top,two bottles. Then pour out 20lbs than take another sample. Each time two bottles. Five samples from different levels in your bucket. Until you you hit bottom. Send out 5 to one assayer, and if you' doubt the results, send five to another. Any large pieces of metal ("gold or silver" that come out of your crusher. Take them out, and do not include in your assay lots). It will screw up your results.

If you you don't have a crusher, get one.( ebay) If you don't have classifier screens, get them.(Ebay) If you don't have the mineral rights to the land, get them. (BLM) Otherwise you're stealing someone else's rock. Show us assays, Prove up what you have, and the guys here will help you retire rich. If you're not willing to do your assays right, just retire now.

Good luck on your venture. Let us know how your assays turn out................................................................
 
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