Watermark Detecting

Hi to all

Not sure if this is in the right place.
I asked a stamp dealer today what he used to find watermarks on stamps.
He told me Shellite is what he uses.

He showed me how he does it.
On a black surface or tray he lays the stamp face down and squirts shellite on the stamp from a small squeeze type plastic bottle and when the stamp is saturated the watermark appears. He was not afraid to show me a couple of times with stamps worth $100.00 each. and it works.
He then takes the stamp in the tweezers and and moves it about and any shellite on the stamp evaporates.

Only thing make sure that you are working in a ventilated area as the fumes can get a bit heady.
I have taken a few pictures of my using shellite, sorry about the clarity/
Shellite is made by the Shell oil company and is a cleaner but it is available in hardware shops in Australia, so probably it would be available in the same places in the USA and UK.
I hope that this is of help
Shellite costs $8.00 A litre so that will last a long time.

Regards

Horamakhet.

Nice pictures Horamkhet. I like the first two. What watermark is this by the way? Crown over CA of the Colony of Australia?

For people in North America the same results are achieved by using lighter fluid (Rosonal brand)(check spelling) or actual watermark fluid sold as that because it is safer to use than flammable chemicals. but more expensive to buy, thus the use of cheaper, more dangerous fluids.

You can also detect some watermarks (marks pressed into the paper during printing) by just placing the stamp on a dark surface face down or even wetting it a bit with water for used stamps only, not to be used with mint with gum.

The watermark fluid or Shellite or lighter fluid will not harm your stamps, used or mint, it evaporates quickly, and it is a good idea to always have good air flow or ventilation to remove the fumes. Do not use around an open flame or sparks or ignition source.

Hi Puzzler

I think it is actually a multiple crown over A which according to Gibbons is watermark 7

As you noted some of the watermarks on some stamps are so good, you can see them on a dark surface or just by wetting. This I notice with a lot of British Commonwealth stamps printed by the Crown Agents.
Regards
Horamakhet

Watermarks are an interesting subject and is one I worked with intensively for many years in pulp/paper mills. Basically there are two methods for creating a watermark. As Puzzler indicated, one is to press a watermark into the paper during the printing process. This is done by the use of a wire design on a roller before the actual ink application to the stamp. The second method is to press the watermark into the wet paper sheet during the paper making process. This is also done by use of a wire design on a roller called a dandy roll. In the customers I worked with, the preference was the method indicated by Puzzler since once the watermark is applied, the paper becomes a type of "security" paper requiring special handling. The later in the process that the watermark is applied, the less security measures needed.