How to tell if antique print is a platinum?

Hello,

I bought a lot of photographs at an antique show and have found two that I

think may be platinum prints. They are very detailed, obviously contact

printed, on fiber paper, cold tone, not a hint of fading, and no silvering.

Nice picture.

Any sure, simple way to determine if an old photo is a platinum?

--- JDR

The image is much more neutral than my scan suggests. No magenta in the

original at all.<div></div>

One obvious hint is any paper in contact with it over time. Platinum is a strong catalyst, often paper facing a platinum print has brown aging marks from the print.

Any sign of a baryta layer would rule out platinum.

You would be looking for a matte surface, a soft grey-black image color.

They got impractically expensive about 1890.

My reference was James M. Reilly, Care and Identification of 19th-Century Photographic Prints, Kodak publication G-25, 1985.

Not hard to find that book used.

According to Webb & Reed in their book 'Spirits of Salts' the way to test if a print is Platinum is to 'place a tiny drop of hydrogen peroxide on a dark corner of the print, and if bubbles rise it is. Then wipe it off. This is a non-destructive test'

Never owned a Pt/Pd print, so I can't do other then point you at the quotation, if it helps. Nick

Hi, Years ago I made a few platinum prints; a hobby that I never persevered with, even though I still have all the chemicals and bits and pieces.However I would say that there isn't enough detail in the blouses or the man's shirt for it to be platinum. There is also not much visible range of tones in the dresses.

It is also fairly unlikely, imho, that the photographer would have taken what is essentially a snapshot using platinum. Think of Frederick Evan's photographs of cathedral interiors as suitable subjects for platinum prints.

From my understanding it was the 1st World War that killed off the process as the military took all the platinum and the price became excessive for the commercial makers who struggled on for a while.

I would say your picture is a toned siver chloride print; toning was often used as an aid to longevity for the image; and as yours is over 100 years old it seems to be working.

Taschen published 'Camera Work' by Alfred Steiglitz as a single volume which has some beautiful images in it.

'The Linked Ring' by Margaret Harker dealt with the Pictorialist photographers who created wonderful timeless images in a variety of artistic mediums including gum as well as platinum.

'The Keepers Of Light' by William Crawford deals with the nuts and bolts of making prints in all sorts of ways.

Early photo manuals like the Ilford Manual of Photography often detailed all sorts of processes very fully, but by about 1935 had begun to drop this sort of information.

There are so many more.

Andy.

My guess is that is a silver chloride print using the Printing-Out Process (POP) which was the

rage during the latter part of the 19th century. Very cheap to produce. Different tones can

be brought about by the use of gold and platinum or if not toned a nice brown color. As far

as

detail goes that is a produce of the negative, a bad negative will not make good a platinum

print but a good negative will make a great print regardless of process or paper.<P>BTW, the

process is still available, one company still produces the paper, Kodak

stopped in the mid 1990's.

Hi,

I read somewhere about the relative abilities of the neg and the print to register detail. If we say a neg can register a range of 1 to 1000, then a standard silver chloride print can register a range of about 1 to 10 and a platinum print can register a range of about 1 to 100. These are very rough numbers but are just to give an idea of what might be expected to be seen when looking at platinum prints. Palladium is a ?cheaper alternative and will produce images of equal tonal range.

Andy.