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| I found these rocks in my yard. |
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| Nonnel:
tried burning it? |
| Juncoph:
--- Quote from: Nonnel on June 17, 2017, 01:47:48 AM ---tried burning it? --- End quote --- anthracite won't burn without a roaring and blown fire op, that stuff looks identical to anthracite sold in bags at tractor supply co --- Quote from: Cappytaino on June 16, 2017, 12:19:17 PM ---If you can write with them, it sounds it could be a kind of coal; higher grade coals (i.e. anthracite and obviously graphite) will leave a trail when rubbed across paper. An anthracite would ignite relatively easily, while a graphite usually does not. The law of superposition would lead me to believe that if you found these on top of or in the A horizon of the soil, they are relatively new, so they could possibly be either slag or mined coal that just got dropped at some point, as the coal could have been used to fire the pig iron forges to make the intermediary product between a mined iron ore and steel. Anthracitic coal will have a hardness of 2.75-3 on the Mohs scale, meaning that you should easily be able to scratch it with a fingernail or a copper coin i.e. a penny. Graphite would be even softer, you could probably scratch graphite with a fingernail. Slag would be harder than anthracite, meaning you'd need a steel file or knife to scratch it. Here's a Mohs chart for reference. [isniptp://www.realgems.org/pic/mohs%20en.jpg[/img] --- End quote --- shiny anthracite isn't scratchable with a fingernail but yeah a copper coin sounds feasible |
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