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How To Read & Understand Drill Results for Mineral Exploration

Mineral exploration drill results can be almost a foreign language. Dig in with Prospector and special guest Kurt Breede to decipher them!

Mining stock investors are often left scratching their heads when companies release drilling results - it's like they're speaking a foreign language!

Between the intervals, grades, widths, and mineralization zones, it's easy to get lost in the data. At Prospector, our goal is to demystify these reports so you can fully understand their implications.

When a mining company reports drill results, it can cause significant moves in the company's stock price, either up or down. This guide will break down the key elements in plain language so you can separate treasure from trash. We'll decode the secret meanings buried in results and give you the tools to make smarter investment decisions when the market shakes amidst the latest drilling announcements.

Don't let confusing data hide potential riches - learn how to read drill reports and uncover the market's most lucrative opportunities!


Why Do Companies Drill?

Geologists don’t actually have x-ray vision (as much as we’d like to think we do), so drilling is an important part of mineral exploration. It is what takes those surface samples and mapping from the initial exploration, and extends them into a 3-dimensional view of the earth above and below the surface. The different types of drilling are used to find the mineralized zone, sample it for its grade (how much of the mineral it is), and establish where exactly the mineralized zone is in depth and area. This helps determine if economically viable mineral deposits exist, and helps decide if a project is feasible.

Drilling can also help geologists establish important information about the rocks that host the minerals, such as rock type, rock quality, relationship between the rock layers, and any major structures which could affect extraction.

Key Terms in Drill Results

Drill results will typically report several key pieces of information including:

  • Interval: The length of the mineralized zone intersected by the drill hole, reported in meters or feet. A longer interval indicates a thicker deposit, which can positively impact potential economics. Intervals of at least several meters are ideal.
  • Grade: The concentration of the target mineral, reported as grams per tonne (g/t) for gold, copper/zinc as a percentage, etc. Higher grades are desirable because they mean more mineral value per tonne of rock. Gold grades above 5 g/t are considered high-grade.
  • True Width: The width of the mineralization perpendicular to the orientation of the drill hole. It compensates for angled drill holes and represents the true thickness of the ore body.
  • Depth: The depth below the surface at which mineralization was encountered. Shallower depths of hundreds of meters may allow cheaper open pit mining. Deeper mineralization over 1000m will likely require underground mining.

Judging Good vs. Bad Drill Results

It can be tricky for non-experts to determine if drill results are good or not. Here are some tips:

  • Compare grades and intervals to previous drill results on the deposit. Are they significantly higher or longer? This adds confidence and size.
  • Consider the likely mining method based on depth. An open pit needs higher intervals + grades than underground.
  • Look at depth. Was mineralization hit at reasonable mining depths <1000m? Extremely deep holes >2000m may not be economic.
  • Check if drilling intersected new zones outside previous drilling, which adds size. Infill drilling within known zones adds confidence.
  • Compare results to similar projects in the region if possible. A new high grade discovery stands out against peers.
  • Monitor share price reaction as a gauge of investor sentiment towards the results.

Ready to dig in?

Drill result announcements can lead to big stock movements for mining exploration companies. While they may seem confusing at first, interpreting the key data points like interval, grade and depth in light of previous results and mining methods being considered will give investors insight into how positive or negative the results really are. Use drill results along with other project specifics to make informed investment decisions.

Looking to keep up with the latest drill results? Be sure to check them out on Prospector News or sign up for our Weekly Data Digest email to have the top drill results delivered to your inbox every week.

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