US Proprietary Stamps Fraudulent Roulettes

At the bottom of the Scott Catalog under RB19 it states "Many Fraudulent Roulettes Exist", so how does one determine between fraudulent roulettes from genuine roulettes.

In addition, how are the fraudulent roulettes made from?

Lastly, I assume genuine roulettes are from the watermarked variety and not from the silk paper variety? Or are they from different parent stock?

Thanks

The perforated proprietaries are frequently found with oversized margins, which provide perfect opportunities for enterprising individuals to cut down and simulate roulettes.

I would not buy either of the big dollar roulettes (RB16c, RB18c) without certs. Mine both have PF certs.

If you see one on silk paper it is obviously a fake.

My examples:










One particular area that I personally am having problems with is telling the difference between RB17 (violet blue) and RB18 (violet). In some cases the RB17 is definitely more blue than violet, but others look *extremely* violet. In fact, if you use the PF certificate search and compare the images of RB17 and RB18, there are some RB17 that look more violet than RB18 shown there. Now one thing to keep in mind: those images were done over the course of 10 years, so there may be variability due to equipment and/or lighting, so those pictures may not be a fair comparison.

I honestly have not looked at enough RB17 an RB18 side by side to be able to tell on my own...

Great thread!
very interesting, and superb scans!
well done.