FMF - Friends of Minerals Forum, discussion and message board

[Jim Prentiss]

Hello Everyone,

I have recently acquired a specimen of Dolomite. I am unable to get a photo of it as I do not have the capability to take pictures of crystals that small.

The label indicates it is from the Wallace Stone Quarry, Huron Co., MI. The crystals are semi-transparent, you can look into the crystal for a bit, light brown, no visible curvature but they are rhombohedrons. There seems to be no deformation, they are clean of any debris. They average 0.2 - 0.8mm (0.008" - 0.032") across. Of the resources availible, including MinDat, I am unable to confirm that Dolomite is found at this location in this quality or color.

Can anyone help out? Or is there some other refeerences on the internet I might access?

Thank You,

Jim Prentiss

[Maxilos]

Hi Jim,

I mostly use books to identify. My book says:
Crystal system: is trigonal.
crystal habit: can be rhombohedral or prismatic.
Colour: White, Gray, Reddish white, Brownish white, Gray
Notable locations: Cumbria, England; Binnetal, Switzerland; Styria, Austria; Saxony, Germany; Pamplona, Spain; Trepca, Serbia; Piedmont, Trentino, Italy; Algeria; Namibia; Brazil; Lake Erie, Ontario, Tristate, Kansas-Missouri-Oklahoma.

So, I would say there is a possebility you can find it there.

You're welcome

Mark

[alfredo]

Steve Stuart put a photo on Mindat of a tiny clear rhomb of dolomite from this locality, and it's not a rare mineral, so why are you doubting that it could be from there, Jim?

[bugrock]

In Michigan Mineralogy (2004) dolomite is recorded from Huron Co:

"The Bayport Limestone (uppermost Mississippian) contains dolomitic beds. Small crystals of dolomite occur with calcite, millerite, and other minor sulfides in quartz geodes at the Wallace Stone Co. quarry, near Pigeon."

This is all that is written there for dolomite in Huron Co, no further description of the dolomite crystals, color or form.

Dolomite is recorded from many Michigan locations.

[bugrock]

For more regarding the Michigan locality including recent finds enter the following location into mindat:

Wallace Stone Company Quarry

It appears Baryte, some interestingly colored calcite (hydrocarbon stained?), and sphalerite are also known from the site. It is a recent source of millerite specimens.

[Jim Prentiss]

Hi Guys,

Thanks for the replies. I have been off the net a few days and appoligize for not getting back to you guys sooner.

I think there is a little misunderstanding. I know Dolomite comes from this location, but what I have is of better quality and different color than any photos published, thus far, on MinDat. I would imagine if there was material this nice from this Michigan location, surely someone else would have published a photo of it. I, unfortunately, cannot as I have no capability, as yet, to do so with my microscope.

I am looking for confirmation that something of this quality and color, actually came from there as there was not a proper label with the specimen, just the name and location written on an egg carton.

Thanks again,

jimp

.

[bugrock]

Jim,

I have no specimens from the location other than millerite and have not collected there. Perhaps someone on the forum can suggest a contact who might know more.

In general though I've noticed many Michigan locations are not well represented by specimen images on mindat.

George

[Jim Prentiss]

Hello All,

Mystery solved. It's Calcite. I played around with it some today and relized I did not fizz test it. When I did, boy, did it fizz, far more than Dolomite. I looked it up and there is a picture on Mindat, listed under Calcite from this location, that is nearly identical to the specimen I have.

Thanks for the replies everyone, I wish I had been more diligent in the beginning.

See ya later.

jimp