<p>I managed to find <em><a href="https://core.ac.uk/download/pdf/297714594.pdf" rel="nofollow noreferrer">EFFECT OF MINERALOGY AND TEXTURE ON THE STRENGTH OF
IRON ORE</a></em>, which states the uniaxial compressive strength of goethite
is  157 kg.f/cm<sup>2</sup>, which <a href="https://www.theunitconverter.com/kilogram-force-square-centimeter-to-megapascal-conversion/" rel="nofollow noreferrer">converts</a> to 15.397 MPa.</p>
<blockquote>
<p>STRENGTH OF ORE</p>
<p>The strength of ore in all the three variants is quite different. Uniaxial compressive strength was found to be 674 kg.f/cm2 for dense martite ore, 254 kg.f/cm2 for microplaty hematite ore and 157 kg.f/cm2 for goethite
ore. In comparison to the reported data on iron ore, the strength of these variants is low to moderate</p>
</blockquote>
<p>Applying the equation</p>
<p><strong>UCS = 1.3672(magnetite percentage) - 3.3093</strong></p>
<p>given in Figure 7, in <em><a href="http://www.zndxzk.com.cn/down/2018/04_znen/JCSU-11771_12-p0795.pdf" rel="nofollow noreferrer">Effect of magnetite content on Bond work index and preconditioning: Case study on Chadormalu iron ore mine</a></em>, for 100 percent magnetite the uniaxial compressive strength would be 133.4 MPa.</p>

CC BY-SA 4.0
2021-12-11T16:46:40.810Z
Much iron ore is now pelletized so it is stronger than the natural minerals.
blacksmith37
CC BY-SA 4.0
2021-12-11T17:11:13.390Z
@blacksmith37: From what I've read, the strength of processed pellets of magnetite tends to be measured in newtons (units of force), whereas the strength of core samples is measured in pascals (units of pressure or stress). The paper referenced for magnetite relates magnetite percentage in core samples to the Bond Work Index that would apply in a processing plant. ...
Fred
CC BY-SA 4.0
2021-12-11T17:11:42.313Z
... "*to study breakage and preconditioning characteristics in the iron ores, two samples with different magnetite percents were blasted by detonation cord. The results showed that with higher percentage of magnetite, the number of fractures induced by blasting increased. Bond work index and magnetite percent were investigated in the 430 blasts in the mine. This investigation not only confirmed the small scale blasting results, but also showed that increasing the magnetite percent up to 50% noticeably reduces Bond work index and energy consumption in the grinding process*."
Fred
CC BY-SA 4.0
2021-12-11T04:03:38.343Z
2021-12-11T04:39:48.833Z
2021-12-11T04:39:48.833Z
Fred
<p>I am attempting to determine what the compressive strengths are of the minerals <a href="https://en.wikipedia.org/wiki/Goethite" rel="nofollow noreferrer">goethite</a> and <a href="https://en.wikipedia.org/wiki/Magnetite" rel="nofollow noreferrer">magnetite</a>.</p>
<p>None of the research I did has proven to be fruitful. What I <em>have</em> found:</p>
<ul>
<li><p>multiple studies regarding what mixing goethite into cement does to the compressive strength of that cement</p>
</li>
<li><p>multiple studies regarding the compressive strength of rocks and ores that happen to have some goethite or magnetite in them, alongside other minerals</p>
</li>
<li><p>a few studies regarding the usage of magnetite in biomedical implants when combined with other materials</p>
</li>
<li><p>multiple studies regarding how goethite effects the mechanical properties of soil, which only mention the mechanical properties and compressive strength of the soil, and not of its individual components</p>
</li>
<li><p><a href="https://royalsocietypublishing.org/doi/10.1098/rsif.2014.1326" rel="nofollow noreferrer">one study</a> involving the goethite found in <a href="https://en.wikipedia.org/wiki/Limpet#Biomineralization" rel="nofollow noreferrer">limpet teeth</a> that only mentions the tensile strength of said limpet teeth, rather than the compressive strength of goethite</p>
</li>
<li><p>no studies or sets of information that actually tell me what the compressive strength of goethite is</p>
</li>
</ul>
<p>Does anybody know what the compressive strengths of goethite and magnetite are, or have a reliable source of information that I can use to find out?</p>

<geochemistry><mineralogy><minerals><reference-request>
What are the compressive strengths of goethite and magnetite?
KEY_ABRADE
# What are the compressive strengths of goethite and magnetite?

(Asked by: username_0 on 2021-12-11)

I am attempting to determine what the compressive strengths are of the minerals [goethite](https://en.wikipedia.org/wiki/Goethite) and [magnetite](https://en.wikipedia.org/wiki/Magnetite).

None of the research I did has proven to be fruitful. What I *have* found:

* multiple studies regarding what mixing goethite into cement does to the compressive strength of that cement
* multiple studies regarding the compressive strength of rocks and ores that happen to have some goethite or magnetite in them, alongside other minerals
* a few studies regarding the usage of magnetite in biomedical implants when combined with other materials
* multiple studies regarding how goethite effects the mechanical properties of soil, which only mention the mechanical properties and compressive strength of the soil, and not of its individual components
* [one study](https://royalsocietypublishing.org/doi/10.1098/rsif.2014.1326) involving the goethite found in [limpet teeth](https://en.wikipedia.org/wiki/Limpet#Biomineralization) that only mentions the tensile strength of said limpet teeth, rather than the compressive strength of goethite
* no studies or sets of information that actually tell me what the compressive strength of goethite is

Does anybody know what the compressive strengths of goethite and magnetite are, or have a reliable source of information that I can use to find out?

**Tags:** geochemistry, mineralogy, minerals, reference-request


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## 1 answers

### Answer by username_1 on 2021-12-11. Score: 5

I managed to find *[EFFECT OF MINERALOGY AND TEXTURE ON THE STRENGTH OF
IRON ORE](https://core.ac.uk/download/pdf/297714594.pdf)*, which states the uniaxial compressive strength of goethite
is 157 kg.f/cm2, which [converts](https://www.theunitconverter.com/kilogram-force-square-centimeter-to-megapascal-conversion/) to 15.397 MPa.

> STRENGTH OF ORE
>
> The strength of ore in all the three variants is quite different. Uniaxial compressive strength was found to be 674 kg.f/cm2 for dense martite ore, 254 kg.f/cm2 for microplaty hematite ore and 157 kg.f/cm2 for goethite
> ore. In comparison to the reported data on iron ore, the strength of these variants is low to moderate

Applying the equation

**UCS = 1.3672(magnetite percentage) - 3.3093**

given in Figure 7, in *[Effect of magnetite content on Bond work index and preconditioning: Case study on Chadormalu iron ore mine](http://www.zndxzk.com.cn/down/2018/04_znen/JCSU-11771_12-p0795.pdf)*, for 100 percent magnetite the uniaxial compressive strength would be 133.4 MPa.

> **Comments:**
> **username_2**: Much iron ore is now pelletized so it is stronger than the natural minerals.  
> **username_1**: @username_2: From what I've read, the strength of processed pellets of magnetite tends to be measured in newtons (units of force), whereas the strength of core samples is measured in pascals (units of pressure or stress). The paper referenced for magnetite relates magnetite percentage in core samples to the Bond Work Index that would apply in a processing plant. ...  
> **username_1**: ... "*to study breakage and preconditioning characteristics in the iron ores, two samples with different magnetite percents were blasted by detonation cord. The results showed that with higher percentage of magnetite, the number of fractures induced by blasting increased. Bond work index and magnetite percent were investigated in the 430 blasts in the mine. This investigation not only confirmed the small scale blasting results, but also showed that increasing the magnetite percent up to 50% noticeably reduces Bond work index and energy consumption in the grinding process*."  

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