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About Us » Writers » Jim Halloran
Jim Halloran
Jim is a consulting placer geologist based in Alaska.

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Articles by Jim Halloran
Reserves and Resources Explained

Reservers and resources are very important to prospectors and miners, but they may be vague terms to some.

February 2014 (Vol. 83, No. 6)
Comments on Gold Rush and Bering Sea Gold Series

The 316 Mining Company has not been all that successful, but does not ever seem to learn from their past mistakes.

March 2014 (Vol. 83, No. 7)
Using Structural Clues to Locate Buried Placer Channels

They must have assumed the paystreak was spotty and had been mined out, so they never mined as close to the side of the valley as they should have.

April 2014 (Vol. 83, No. 8)
Exploring Placers with Auger Drills

Augers can be used effectively for placer exploration with certain limitations.

June 2014 (Vol. 83, No. 10)
Using Vegetation and Soil Conditions as Prospecting Aids

Wouldn’t it be great if you could know if there is gold in the ground without setting foot on the ground? Well you can, to a certain extent, if you can recognize mined ground from unmined.

January 2013 (Vol. 82, No. 5)
Benches and Fossil Placers

Unfortunately for us mortal humans, we have a poor perspective on geologic time. When we look at a landscape such as a stream valley, we see it only in two, or at the most, three dimensions. We have poor comprehension of the valley’s fourth and most important dimension—time.

March 2013 (Vol. 82, No. 7)
Excavator Testing Wet Placer Ground

The excavator or backhoe has become the tool of choice for testing placer ground. These machines are the best way to explore and sample a placer deposit if the ground is not too wet or frozen and bedrock is not beyond the reach of the machine.

April 2013 (Vol. 82, No. 8)
Advantages of Modern Prospectors

Modern-day placer miners have many advantages over the prospectors of the gold rush days. Our prospectors can reap many benefits from accumulated knowledge of the last 100 to 150 years, which is a long and impressive list.

May 2013 (Vol. 82, No. 9)
Confluence Placers

Confluences of placer streams are well known as concentration sites for heavy minerals. The basic reason is that...

June 2013 (Vol. 82, No. 10)
Placer Channel Sampling

Sampling gold placers can be rewarding, but remember to treat the samples so you are not high grading or low grading your results. Learn the rules and apply them so your samples are accurate.

July 2013 (Vol. 82, No. 11)
Sampling Placer Stockpiles

Sampling other people's stockpiles or dumps has some inherent risks that sampling undisturbed ground does not have.

August 2013 ( Vol. 82, No. 12)
Proper Spacing of Placer Sample Sites

The zone of influence of each sample must be carefully considered when deciding how far sample sites should be spaced from each other.

September 2013 (Vol. 83, No. 1)
Proper Placer Sample Processing

...your sampling procedures should not be designed to catch gold your mining technique will never recover.

November 2013 (Vol. 83, No. 3)
Fine Gold Panning Without Using Mercury

The technique I will describe is a much safer alternative and it works. It’s a fine-gold panning technique that eliminates the need for mercury amalgamation of most placer samples.

March 2012 (Vol. 81, No. 7)
Bering Sea Gold—Part I

The popularity of the new Discovery Channel series Bering Sea Gold has peaked interest in what gold resources are offshore of Nome, Alaska. The Cape Nome mining district is world famous...

April 2012 (Vol. 81, No. 8)
Bering Sea Gold—Part II

In last month’s issue we covered the initial discovery of gold, the subsequent gold rush that occurred around Nome, some of the geology of the area and past production. We’ll conclude the article in this issue with a further examination of the geology and deposit types, discuss the resources...

May 2012 (Vol. 81, No. 9)
Gold Deposition and Gradients of Placer Streams—Part I

When placer miners from the gold rush era began experimenting with the slope of their sluices, they must have pondered the ideal slope for trapping gold in a creek bed too. Logic suggests the same is true for streams...

June 2012 (Vol. 81, No. 10)
Gold Depositiion and Gradients of Placer Streams—Part II

The steeper the gradient is, the more potential erosive power to move gold and other bedload sediments, and the more power to remove obstacles to flow.

July 2012 (Vol. 81, No. 11)
Potholes and Other Bedrock Traps

Potholes in bedrock can trap placer minerals and even be glory holes. They are, at least, interesting geologic phenomena, and at best, a treasure trove of gold nuggets.

September 2012 (Vol. 82, No. 1)
Proper Assaying of Placer Samples

The whole purpose of sampling mineralized ground is to measure the values in a small volume of material that would be representative of a much larger volume of similar material. The key word is representative. Chemical and fire assaying will not accurately represent placer deposits by themselves.

November 2012 (Vol. 82, No. 3)
Scams, Scammers and Schemes

Gold mining has received many black eyes from many scams, scammers and schemes throughout the years. Unscrupulous scammers have swindled naive people for millions of dollars in the past and will, no doubt, continue into the future.

December 2012 (Vol. 82, No. 4)
Prospecting With The Help of Fluvial Geomorphology

Quiz yourself about the stream in figure 5. Based on your previous knowledge of where gold is found in a stream and in this article, where do you think you will find the most gold?

March 2011 (Vol. 80, No. 7)
Why Haven't They Mined This Claim?

Improvements in mining equipment and techniques, along with a higher gold price, make many mining properties profitable today that may not have been in the past.

May 2011 (Vol. 80, No. 9)
What Are Those Rocks In My Pan?

The placer mineral identification key is designed to answer this question. It attempts to recognize all the minerals in your gold pan concentrates.

June 2011 (Vol. 80, No. 10)
"Gold Rush: Alaska" in the Porcupine Mining District

Honestly, I don’t believe it is likely there would be a glory hole where they described one at the bottom of the waterfall because plunging water with enough energy to scour out a large hole in bedrock would have the scouring ability to grind up and...

June 2011 (Vol. 80, No. 10)
Understanding and Prospecting Benches

The most obvious benches are usually near the valley floor, but they can be thousands of feet above the valley floor. Since benches were made by streams, they can contain placer deposits.

September 2011 (Vol. 81, No. 1)
The Fine Art of Panning Heavy Sands

The fine art of panning heavy sands requires a measure of patience. If you enjoy panning gold, you ought to enjoy this too, once you get the hang of it.

October 2011 (Vol. 81, No. 2)
Alaska's Cripple Creek Mining District

If developed with metal detecting in mind, this virgin ground could be a bonanza for nugget hunting.

November 2011 (Vol. 81, No. 3)
The Significance of Boulders in Placer Deposits

The good news about boulders is they can trap heavy minerals. The bad news is moving them out of the way can be a real struggle.

February 2010 (Vol. 79, No. 6)
Glaciers and Placer Gold Deposits

Here we examine where and why placers are found in glaciated landscapes from the Ice Ages.

June 2010 (Vol. 79, No. 10)
The Curious Saga of the Jack Wade Creek Dredge

As the river dredgers soon learned, it was not a good idea to leave your dredge in the Fortymile River over winter.

July 2010 (Vol. 79, No. 11)
Alaska's Hope-Sunrise Mining District

Over 100 years of placer mining on the Kenai Peninsula has produced about 133,800 ounces of gold. Hard rock mines produced an additional 30,000 ounces. Suction dredging is currently the dominate mining method.

September 2010 (Vol. 80, No. 1)
Recreational Mining in the Cache Creek Mining District, Alaska

The mining district is more than 110 years old, but the two recreational mining areas are new. The State of Alaska designated the Petersville Recreational Mining Area within the past year and the Alaska Gold Mining Camp is not much older, so you can expect to find some unmined ground!

October 2010 (Vol. 80, No. 2)
Undiscovered Placer Deposits in Alaska

These conditions don’t just apply to Alaska and the Yukon; they apply to western Canada and even to the mountainous western United States.

November 2010 (Vol. 80, No. 3)