Hi,
Frank Spear and I published on cld rx from western NH in 1993 (j pet) but these have a very different texture. Similarly Thompson and Leclair (1987) describe more complex assemblages from Ontario, but these appear to have a different texture also.
Other cld schists at Orfordville NH are black with graphite. Probably not your rock.
Maybe schists from Salmon Hole Brook Syncline (cf. Florence et al., 1993 - we didn't analyze them but they're there)? Those also contain biotite, but not so much graphite. The beds are noticeably graded, also.
Matt
Sent from my iPhone
On Jan 28, 2012, at 5:36 PM, Horst Marschall <[log in to unmask]> wrote:
> Hi Barb,
>
>> On 28 Jan 2012, at 17:16, Barbara L Dutrow wrote:
>>
>> Why do you think it was sourced from here? Could it b from Canada?
>> B
>
> You mean those natives smuggled rocks accross the border thousands of years ago?
>
> But seriously, of course anything on the Ontario or Quebec side would probably also be in the range of those trade routes. The artefact wa discovered in the Connecticut River Valley in western Massachusetts. And because chlortoid-garnet-mica schists have been described from New England, I thought that area could as well be the source of the rock. But, please send me your suggestions for localities further north.
>
> cheers,
> Horst
>
>
>
>> On Jan 27, 2012, at 2:46 PM, "Horst Marschall" <[log in to unmask]> wrote:
>>
>>> Dear community, especially New England petrologists,
>>>
>>> we are in need of a list of localities in New England where this rock type occurs:
>>>
>>> quartz-chloritoid-garnet-muscovite schist ±graphite
>>>
>>> The garnet is less than half a millimeter, but clear, red and euhedral. The black chloritoid blasts are larger than the garnet (2-3 mm). The slightly greyish colour of the mica-rich groundmass points to graphite.
>>>
>>> I'm sure someone on the list can easily point out a few localities between MA, VT, NH or ME (or NY) where this type of rock is common?!
>>>
>>> many thanks in advance,
>>> Horst
>>>
>>>
>>> PS: This rock was made into an artefact of archeological value and can't be made into a thin section. No whole-rock analysis either. I haven't even seen a very fresh surface.
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