FMF - Friends of Minerals Forum, discussion and message board

[fuss]

Hi all, I'm new to rock and mineral collecting, so please understand my ignorance on the subject. I found this in north central Wisconsin and thought it was granite, but after some web research I am now guessing it could be Miserite? any help is appreciated.

[Bob Carnein]

This is a tough one to identify from a photo. Can you tell us where in Wisconsin this came from? Miserite is not a common mineral; I'm curious to know how you decided it might be that?

[lluis]

Hi, fuss

Even not looking as mine example, Wisconsin certainly have Miserite.
If yours is miserite, maybe... An analysis is a must in this case,
By the way, granite is a rock and miserite a mineral....

May you give us hardness, color of streak, density, place of find, anything more?
As warlock.I am just a misery... (not a miserite....)

With best wishes

Lluís

[fuss]

Thanks Bob, It came from Langlade County WI, on my father-in-laws property. I was collecting interesting glacial till rocks and saw this and thought it was an interesting chunk of granite. After looking at it closer it does not look similar to other granite rocks in the field and so I did a a bit of google searching and thought it resembled the Miserite I found on the Wisconsin Geological and Natural History web site.

[fuss]

Hello Lluis, I scratched it with a knife easily as well as a piece of beach glass I have here. I don't have any unglazed ceramic on hand to do a streak test, can I test on something else?

[lluis]

Hi, Fuss

Miserite could not be scratched by a knife
Glass should also not... Then, I have a trouble....
Or I should understand that a beach glass scratch also the pink stuff?
If glass scratch the pink stuff and a knife not, then could be miserite...

For scratch line, if you can say which is color of dust, well, that is same.
If white, could continue being miserite...., I think


Also, you could so a flame test: it should have a red flame... Indicating calcium.
But that is not too reliable Or the violet of Potassium (easier to see,,,,).
If it shows so, it maybe miserite..... If not, and is first time you did, it could be also miserite....

Maybe you could do also a density of dust of pink stuff....
If very close to miserite, then maybe miserite.....

With best wishes

Lluís

[fuss]

Lluis, I will do the scratch test again after work today and post pictures, I ordered some streak plates that will be here in a couple of days. Also please explain the burn test, should I hold a lighter to a portion of the rock? Thanks much.

[Bob Carnein]

Miserite's hardness is 5.5-6; because of its habit, and because of differing hardnesses of steels, you may be able to "scrape" it with a knife, leaving a mark that looks like a scratch, even if the knife doesn't truly scratch it. Always turn the test around and try the specimen on the knife blade, and put pressure on it. With glass, of course, always try scratching the glass with the specimen, rather than the other way around.

[fuss]

Update, I picked up some black and white streak plates and some glass and did the test.
It does scratch glass and the streak is pinkish/white.

[lluis]

Hi, Fuss

I suppose I made a lexical mistake.... For burnt test I tried to say "flame test"
You pick some powder of the mineral to be tested with a platinum wire (or a nichrome wire which is far more cheaper....), a drop of clorhidric acid, and place it in the flame of a Bunsen burner. And look at the color that flame gets....
Sodium gives a very strong yellow color that could mask potassium violet (that should be then looked through a blue filter (a pot of copper diammin sulphate solution (copper sulfate in water, plus some ammonia, till a dark blue colour....) will go...)

But this should be done in a lab, and is recommended that the tester has experience.
The reagents are not very dangerous, but should be handled with care...

On streaks...
I think that miserite does not scratch glass.
Streak could be that of miserite.
Maybe the scratch in glass is due to differential hardness.....

Maybe Alfredo could place more light on this...

With best wishes

Lluís