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[auscarver]

I found this deposit last Christmas. It has taken me months to sort out how to polish this iron based stone.it’s around 6 to 6.5 hardness and does contain quartz and rhyolite in the mix. I polish on a 50k diamond belt followed by super cerium oxide.

[lithicbeads]

Beautiful. On the west coast of north America it is associated with iron and manganese in a number of cases and I have found it intruding phyllites.A spot  where we were at last week it occurs where basalt and argillite are mixed at high temperature. Most of the poppys are within a few feet of the basalt with other jaspers being common  on the argillite side of the mix.

[vitzitziltecpatl]

Looks good! Can't go wrong with red on black, right?

Have used 50K diamond on felt (with a few extra drops of extender fluid to keep it slick) on some problem stones. You got a nice finish on that one with your belts. I use the felt on a flat lap so I can vary the speed as needed.

You sure do come up with some interesting material there. It's always a treat to see your latest discoveries.

[auscarver]

Thanks for the great feedback. This to is associated with Basalt, clinoclorite, and a chatoyant white quartz looking material. It’s in contact with the basalt. Manganese only around150 M away with rhodonite, prehnite about 1 km in contact with gneiss.

[AgateLicker]

Stunning material! Please don't hesitate to drop any more info regarding constituent minerals and relationships.

The iron matrix almost looks like it's chatoyant in the photo. Got a velvety look going on. Are the grains oriented specifically or is the light playing tricks on me?

Forgive my ignorance, but in what ways was it a problem stone/material?

[lithicbeads]

Is the matrix specular hematite?

[auscarver]

Today I went back, well it contains what I think is both magnatite and hematite, most of the black base stone is very magnetic, but it does contain seams of silvery crystal material that is not magnetic that could be specular hematite, it has a reddish streak, the silvery material looks like mica. Most of the black base leaves a black streak.

[auscarver]

Specular hematite, does this look correct. The reddish maroon stone has a brown red streak on a streak plate but the clear white leaves no streak, harder than the plate. Scratched it. This stone is in contact with the obicular material. Along with clinoclorite and basalt, and quartz.
ED82CB6F-855B-4066-80B7-13EF9ECE0DFB.jpeg (977.09 kB . 1724x1579 - viewed 1229 times)

[AgateLicker]

Any idea what the age of the formation is? This smacks of Mesoproterozoic diagenetic mineralization. The flashy metallic could very well be grading towards ilmenite, a titanium iron oxide. This chart came into my life recently when investigating the Del Rio Quartzite from Yavapai co. AZ.

[lithicbeads]

There is a conglomerate in Mississippi and a few other southern states that has an ilmenite- specular hematite matrix which is black at most angles but silver at a few. The non matrix is quartz from Wisconsin and limestone from the Ohio river valley. I have posted stones cut from it as Aunt Helene's Mississippi peanut butter brickle stone  which describes it's look as well as it's collector.

[auscarver]

The nephrite jade in my region is approx 380 million years old. and this is only a few Km from that on the same fault. I have no dought it has magnatite and hematite in the mix as the streak test conferms both. And clorite- clinoclorite that has been tested by xrd, I have a copper deposit close by as well as a manganese one with rhodonite.
The crystals in the picture are harder than 7 as it easily scratched the streak plate.

[auscarver]

A picture of a piece I cut yesterday that has the clorite and the silver white material in the stone.
890F3309-6312-495E-896E-FCE21C8CA22D.jpeg (246.06 kB . 668x1034 - viewed 1193 times)

[vitzitziltecpatl]

There is a conglomerate in Mississippi and a few other southern states that has an ilmenite- specular hematite matrix which is black at most angles but silver at a few. The non matrix is quartz from Wisconsin and limestone from the Ohio river valley. I have posted stones cut from it as Aunt Helene's Mississippi peanut butter brickle stone  which describes it's look as well as it's collector.

Your Aunt? We were lucky enough to get a chunk of that rough from someone in Mississippi. It's the only piece we've ever seen in person.

[lithicbeads]

Not my real Aunt just a friend. She has found lots and there is a crap load of carnelian down there , it's all over in any gravel.

[R.U. Sirius]

Do we know what the white crystals are (harder than 7)?