Meteorite-odd resistor

[TinMan]

So my friend on a farm dug up this rock with his hoe behind a tractor. the odd thing is that the paddock has nothing but sand and grass in it-->no other rocks or stones have been found in the paddock. he seems to think it is a meteorite,and i must say,i haven't seen a rock quite like this one-->or a mixture of what ever it may be.The rock is about the size of a football,and he broke one piece of for me to take home. It is that hard,my dimond cutting disk hardly marks it. Anyway,i been doing some testing on it,and have found some odd resistive properties with it.

https://www.youtube.com/watch?v=OI9PWViGAXQ

[TinselKoala]

I think I have a chunk of the same rock!

That is, it looks very much like the Lead Galena pieces that I have on hand here.

Nonmagnetic, conductive/resistive qualities match. It will take me a little while to construct a holding jig and to perform the other tests with voltage that you have done.

How it came to be in your friend's sandy paddock is another story. Could he be pulling your leg? Did he give you the rock on the first of April by any chance?

[BEP]

Revealing a bit about me...

If I had followed my forefather's I would be a fifth generation blacksmith. My Dad had chunks of stuff that looked the same in varied sizes. It was galena. He used it (when I was really young) to make fishing weights. Farmers used it for much the same -- lead shot, weights, sealing cast iron pipes. I doubt the common by use of galena by farmers went much past the early 20th century in the US.

I tossed about 25lbs. of it when I cleaned out my parents house.

[TinMan]

Revealing a bit about me...

If I had followed my forefather's I would be a fifth generation blacksmith. My Dad had chunks of stuff that looked the same in varied sizes. It was galena. He used it (when I was really young) to make fishing weights. Farmers used it for much the same -- lead shot, weights, sealing cast iron pipes. I doubt the common by use of galena by farmers went much past the early 20th century in the US.

I tossed about 25lbs. of it when I cleaned out my parents house.

Well im not sure that it is galena,as it is very hard,and brittle,and im not sure how you would make fishing sinkers out of it,or use it as lead shot. Slider thinks it may be antimony ?. It dose seem to have semiconductor properties,and shows a strong diode value. But it is the voltage and current that can be meassured all around the object that has me intrigued


@TK

No,he didnt give it to me on the 1st of the 4th lol.I got it over a month ago,and only now have decided to have a closer look at it.

[Slider2732]

Yeah, check out the Wiki:
https://en.wikipedia.org/wiki/Antimony

I tested the resistance and the piece here measures around 1ohm, which is though slightly lower than the space rock.
It's non magnetic (actually diamagnetic), weighs similarly to perhaps steel. It has a really good silver shine on it and yet what seem to be facets.
Australia does have export worthy amounts I noted, so it is possible to be natural, if antimony. Space rock sounds better though and it still could be...a bunch of stuff has fallen on the planet over the years.

*Edit* - That lead galena does look highly similar, now that i've watched the video again.
Hmmm, if i'm no good as a metallurgist, i'll settle for being a lurgist of something else

[TinselKoala]

Well, I made a little jig to hold my chunk of Lead Galena tightly between a couple of springs. I then connected it to my power supply in series with a car brake light bulb, and gave it enough voltage to light up the bulb dimly. Then I probed with a 3-LED tester.

I got slightly different results: I did see a gradient across the sample, where Tinman didn't, and the LEDs wouldn't light when probed very near the terminal like his did. The sample did get warm during the testing; its resistance is a bit higher than what Tinman measured.

So now I'm trying to find my little DC motor in all the mess, just in case the motor commutation has some effect on the voltage gradient, or non-gradient, across my sample.

[Slider2732]

A test from over here with Antimony.
Wall adapter, 12V car bulb.

Every place tested returned the same figure of 6.44V or 6.43V
Right next to the terminal, or behind it shows the same reading.
Am not sure i've got a 6V motor, being that nearly all that have wire left on their stators are single cell R/C related in this house.
But....maybe the look-a-like traits to galena could come from the tractor scraping the rock with its equipment. When scraped, antimony has a similar flatter facet metallic sheen (a pic above shows that at the base).

[TinMan]

Here is another look at the space rock,although it's looking more like antimony as Slider said???.

https://www.youtube.com/watch?v=t2K3Tx5X37c

[TinselKoala]

I tried again, and was able to reproduce the LED probe result with probe near or even behind the terminal, as Tinman showed... but only for a few seconds, until the sample warmed up from resistive heating. My sample is pretty small and heats up rapidly; it measures about 15 ohms or so in the spring-jig. Once it's hot, I just see a "normal" voltage gradient across it as one might expect.

So far, it looks like the Antimony sample matches TinMan's results more closely than my Galena sample. But what's a big chunk of antimony doing in a sandy paddock?

Maybe some exploration out there would reveal a "motherlode" of pure antimony chunks.....

[Slider2732]

Haha, indeed, the elephant in the room being the elephantine chunk itself !

TinMan - your buddy may become a rich farmer  
At least someone may want to buy the rights to that local area of land for exploration (an Aussie company of course, none of that foreign muck).
Being as you guys even have a few million hectares to devote to the exact placement of an outside toilet, he could do very well for himself and also keep on farming.

The double diode effect and negative voltage disparity shown on your scope was peculiar. How does reversing something give a very similar result. I expect it has to do with how the rock treats any energy, no matter the source or direction. Seems it uses heat as a 'control valve'...most peculiar indeed.
What can we do with that ?

[TinMan]

Haha, indeed, the elephant in the room being the elephantine chunk itself !

TinMan - your buddy may become a rich farmer  
At least someone may want to buy the rights to that local area of land for exploration (an Aussie company of course, none of that foreign muck).
Being as you guys even have a few million hectares to devote to the exact placement of an outside toilet, he could do very well for himself and also keep on farming.

The double diode effect and negative voltage disparity shown on your scope was peculiar. How does reversing something give a very similar result. I expect it has to do with how the rock treats any energy, no matter the source or direction. Seems it uses heat as a 'control valve'...most peculiar indeed.
What can we do with that ?

Well im not sure what we could do with it,but i do know that it heats up quite a bit with very little current. And it seems the hotter the rock gets.the lower the resistance across it.

[Chet K]

Do a Kenny Wheeler......
??
see if it gets hot....?

[TinMan]

Do a Kenny Wheeler......
??
see if it gets hot....?

Lol-yea,sure ,why not. I'll go stick a neo on it righ now .
The interesting thing is,i know of no other substance of that much mass that can be heated up so quickly on such low power level's. Infact,i was thinking of sticking it in a ltr of water,and do a calometric test,but i need Steve to remind me of how many watts for how many minutes to raise the temperatur of a ltr of water by X? amount-as i forgot lol.

[Chet K]

OOHHH
I like that Idea ...A LOT

solar panel paint.....[heat exchanger panels]