Black mica?
 

Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Black mica?
 

On Thu, 03 Nov 2016 16:41:17 +0000, N_Cook wrote:

Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Intrusions or *inclusions* do you mean?

Black mica?
 

On 03/11/2016 17:22, Cursitor Doom wrote:
On Thu, 03 Nov 2016 16:41:17 +0000, N_Cook wrote:

Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Intrusions or *inclusions* do you mean?


I'm no geologist, not erratics anyway.
Randomly distributed swirls like colours in marble, but smokey black colour

Black mica?
 

On Thursday, November 3, 2016 at 9:41:15 AM UTC-7, N_Cook wrote:
Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Sure; Amelia County, VA has some old mica mines, the native stuff is near black
(but that's 0.3 inch thick, and it's prepared by cleaving down to 0.003"
thickness).

Black mica?
 

On Thu, 3 Nov 2016, whit3rd wrote:

On Thursday, November 3, 2016 at 9:41:15 AM UTC-7, N_Cook wrote:
Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Sure; Amelia County, VA has some old mica mines, the native stuff is near black
(but that's 0.3 inch thick, and it's prepared by cleaving down to 0.003"
thickness).

So it's just availability? There's no special quality of black mica over
the regular stuff?

Michael

Black mica?
 

.....Just paint it black !

N_Cook a écrit :
Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Black mica?
 

On 04/11/2016 01:15, whit3rd wrote:
On Thursday, November 3, 2016 at 9:41:15 AM UTC-7, N_Cook wrote:
Anyone ever seen this before? Basically clear mica but with black smokey
looking intrusions, something geological in the way of tar/bitumen
leeching into the cleaving planes?

Sure; Amelia County, VA has some old mica mines, the native stuff is near black
(but that's 0.3 inch thick, and it's prepared by cleaving down to 0.003"
thickness).


I don't suppose you happen to know whether the insulation property is
just the same? I'm thinking whether the black material may absorb water
vapour

Black mica?
 

Pretty much all questions answered right he

https://en.wikipedia.org/wiki/Mica

Ontario seems to be one source of "Dark Mica".

Some types do absorb moisture, but, it is not as if they would be used for insulators.

The original "Glitter".

Peter Wieck
Melrose Park, PA