Booklet Covers And Panes

Hi all,
I have a couple questions for the forum on this subject. As I go through this mass collection, I have run across several of the samples below. I believe the stamps to be 319g type I, and the cover itself to be the corresponding BK17 (front and back) that would have been purchased as a complete set. The watermark is the vertical 191, though it is inverted. You may notice some white poking out from the perf holes top and bottom. This I assume is from some type of hinge, not similar to other hinge remnants I have seen.

My questions are;

1. What is the significance of and inverted watermark
2. Is the CV value (used loosely) for the "complete" booklet
3. Why would a collector separate the booklet cover from the stamps

Thanks again!

Not sure about the first two questions, but the collector possibly removed the cover so the pane could be displayed in the album with the stamps showing (as evidenced by the possible hinge marks).

Just a guess..

The vertical watermark is normal for early booklets. The early booklet panes wer printed from either 180 subject (10x3 pane arrangement) or 360 subject (10x6 pane arrangement) and the sheets were provided cut to size to the Bureau with the vertical watermark.

Since there was a readily visual indicator of top or bottom of the sheet of the roll face or reverse the watermark can be one of 4 orientations:
Normal
Reverse
Inverted
Reverse inverted.
All orientation are relatively common.

The BK17 complete is about $3250 for Type I with recent aution sale at $900-1400, Type II $12,000 with recent aution sales ate $3500.

As stated previously, displaying the stamps may have been one motivation. I'd also like to add that this booklet contained 8 blocks of 6 stamps, stacked on top of each other, and if the collector is like me, he may have been nervous about leaving them stacked together in booklet form. Finally, staples from this era do not fare well after so long a time. It may be that someone didn't want them to rust and simply removed them for that reason.

I do not know if removing these stamps from the booklet affects the value (assuming you have all the contents of the booklet, still). Perhaps someone else can weigh in?