<p>I'm trying to acquire an understanding of how the difficulty of prospecting for useful ore has increased over historical timescales.</p>
<p>Intuitively, I would expect that centuries or millennia ago, you could find deposits, at least of common things like iron and copper, just by walking around looking at rock formations, whereas nowadays those have all been discovered, and to find anything new would take a team of experts carefully analyzing subtle clues from geological maps, perhaps with the aid of exotic instruments like gamma-ray spectrometers.</p>
<p>Is this general intuition correct? If so, are there any available numbers, even plausible estimates, for how much the difficulty has increased in quantitative terms? Anything like 'in preindustrial times, the average prospecting effort to find an iron ore deposit was X months; by 1800 it had increased to Y months'?</p>

CC BY-SA 4.0
2021-03-26T13:49:10.077Z
I'm not a geologist at all, but as for your second paragraph, I would expect that modelling where deposits are expected is a crucial part of modern prospecting.
gerrit
CC BY-SA 4.0
2021-03-26T16:07:34.277Z
Related to [How do geologists find ore deposits?](https://earthscience.stackexchange.com/questions/4848/how-do-geologists-find-ore-deposits?rq=1)
Fred
CC BY-SA 4.0
2021-03-26T16:17:19.783Z
Your intuition is correct most surface occurrences of mineral deposits have been found or mine. These include [outcrops](https://en.wikipedia.org/wiki/Outcrop), [gossans](https://en.wikipedia.org/wiki/Gossan) & [placer deposits](https://en.wikipedia.org/wiki/Placer_deposit). Discovery these days usually involves drilling of magnetic anomalies, depending on what metal is being sought.
Fred
<geology><minerals><economic-geology><ore>
Ore prospecting and the low-hanging fruit effect
rwallace
# Ore prospecting and the low-hanging fruit effect

(Asked by: username_0 on 2021-03-26)

I'm trying to acquire an understanding of how the difficulty of prospecting for useful ore has increased over historical timescales.

Intuitively, I would expect that centuries or millennia ago, you could find deposits, at least of common things like iron and copper, just by walking around looking at rock formations, whereas nowadays those have all been discovered, and to find anything new would take a team of experts carefully analyzing subtle clues from geological maps, perhaps with the aid of exotic instruments like gamma-ray spectrometers.

Is this general intuition correct? If so, are there any available numbers, even plausible estimates, for how much the difficulty has increased in quantitative terms? Anything like 'in preindustrial times, the average prospecting effort to find an iron ore deposit was X months; by 1800 it had increased to Y months'?

**Tags:** geology, minerals, economic-geology, ore

> **Comments:**
> **username_1**: I'm not a geologist at all, but as for your second paragraph, I would expect that modelling where deposits are expected is a crucial part of modern prospecting.  
> **username_2**: Related to [How do geologists find ore deposits?](https://earthscience.stackexchange.com/questions/4848/how-do-geologists-find-ore-deposits?rq=1)  
> **username_2**: Your intuition is correct most surface occurrences of mineral deposits have been found or mine. These include [outcrops](https://en.wikipedia.org/wiki/Outcrop), [gossans](https://en.wikipedia.org/wiki/Gossan) & [placer deposits](https://en.wikipedia.org/wiki/Placer_deposit). Discovery these days usually involves drilling of magnetic anomalies, depending on what metal is being sought.  

---

## 0 answers

