The demand for such items is always here Archive of auctions (2009 ) http://www.kabinet-auktion.com/auction/9287/
Here are the results of auction

Вложение 1526371

Lot number 1 sold for , 170t . (similar to your)
Lot number 2 sold for -320 m
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Your letter of (my opinion) is not less than 100t.rub.Restavrirovat not. ( Who will buy will decide to make a passport and a frame or put in a folder )

PS Maroussia, you have a very interesting object of curiosity .. I congratulate you on your discovery .

Can understand.
On the parchment folds and creases are soft, almost like the fabric and on paper - sharp.
Parchment silky to the touch, the paper - rough.

Old parchments, I would say, shaggy-velvet <! - ~ 7 ~ ->

That's so ...

And yet, the "old parchment" gives a feeling of indescribable: if you hold in their hands, "a piece of history" ...

Today there was an auction, "Mark", 4:00 enjoyment.

Review will try to write on Monday.

As for the parchment spoke with a very correct person.

So - with an autograph letter of Catherine is in the range 2000 - $ 10,000 depending on the state.

Constantine had already talked about it (the price depending on preservation ):

The lower limit , so designated , but the upper $ 10,000 on my no.
Yesterday at an auction , my neighbor fought for two standard photographs, the two princes. How many have bought do not remember , but the estimate exceeded once in five or six (or rather write in a review , so I do not remember ). In a break with him talking to the question why he standard portraits ( as is usually claimed unusual camera angles ) suddenly told me a story about two people in the photo , and that served in a cavalry unit, and he collects all that is associated with this subdivision . It became clear that no , he could not buy . Yes, and autographs on the photos were.