ATTENTION: After years of printing paper photographs in platinum, gold, rhodium, palladium, and iridium, I am abandoning that work. As of the summer of 2023 I have been devoting my efforts exclusively to printing on fabric -- fine linen, Egyptian cotton, and silk. Refer to the image, below, of the Alamo printed on habotai silk. As a consequence this site will vanish in March 2024. My future work will be hosted on Facebook as Richard Eugene Puckett. Printing the noble metals on silk and other fabrics is extremely costly, as 5 to 6 times more metal must be applied to the fabric, and I do not anticipate any followers down this path; therefore I will not bother to prepare any materials guiding would be printers through the many nuances one must observe successfully to print on fabric -- just preparing ammonium or sodium ferric ferrous oxalate, mixing it with palladium and pouring the solution onto a piece of silk or linen will not suffice to obtain a desirable image.

FREE PDF: 21st Century Alchemy: Gold, Rhodium, Platinum, Palladium, and Iridium (and Nickel)

  

The Alamo, Nickel-Palladium on Habotai Silk

The short documentary, Magic Iron Rose, about Richard Eugene Puckett's relentless quest to work out a formula for printing out rhodium, won a Remi at the 2017 Houston WorldFest. Click on the image below to view the film.

* The Rhodiotype is the first, the only process in history, for printing photographs in rhodium.

* The Palladiotype Supreme and the Platinotype Supreme are the first and only processes for dry print out with those noble metals -- no hydration of paper, no learning curve, no wasted money time: prepare the sensitizer, apply it to the paper, let it dry, print it out. 

* The Ultimatype resolves an impossible combination: gold and platinum printed together not for special effects but for continuous tone grayscale images that exploit the finest qualities of both metals.

* The Auridiotype combines gold and iridium for astounding results not obtainable by any other process.

Full List of Richard Eugene Puckett's Processes

Glass Coating Rod circa 1890, a century before its invention by Mike Ware : William Willis, inventor of the platinum printing process, specified that the admixture of ferric oxalate and potassium platinum chloride should be applied to paper using a glass coating rod wrapped with flannel. Any expert on platinum would surely have read Willis' third and final patent application for platinum printing and know better than to use a plain glass rod for applying platinum or palladium sensitizer to paper.

• Ultimatype Supreme: continuous tone, gray scale gold and platinum, DPO. Imagine a silver gelatin print with wider latitude, deeper 3D dimensionality, and a captivating luminous glow.
• Platinotype Supreme: pure platinum DPO,  may be mixed with palladium or iridium (this process is somewhat different from Pizzighelli's formula). This is the only print out process for platinum that actually works. Consider that the 1887 formula*, below, developed by two Austrians -- a professional chemist and a photographer -- worked; it took a Scottish university don and a Tanzanian photographer years of goofing around with it sufficiently to make it not work...
• Palladiotype Supreme: pure palladium DPO, may be mixed with platinum and/or gold and/or iridium and/or rhodium. This and the Chrysotype Supreme constitute the simplest printing processes with the noble metals.
• Rhodiotype: rhodium DPO, two versions: one pure rhodium and the other using a small volume of palladium chloride to catalyze reduction of the rhodium. The palladium serves no more purpose than does the iron in the sensitizer, and is optionally dissolved with a hydrochloric acid bath after print out, leaving a print that XRF spectrometric analysis has shown to be above 90% rhodium.
• Iridiotype: iridium DPO, two versions: one pure iridium and the other using small volume of palladium chloride to reduce and smooth the iridium.
• Auridiotype Supreme, DPO gold and iridium: the single sole process for printing gold mixed with iridium. The images printed reveal an almost technical precision of detail combined with a superb tonal range. 

* Pizzighelli's 1887 formula (redacted from The Dictionary of Photography for Amateur and Professional Photographers, London, 1902):
1. Prepare a 50% solution of gum arabic,
2. Prepare a 40% solution of Ammonium Ferric Oxalate )blue-gray tone) or of Sodium Ferric Oxalate (brown-gray tone)
3. Prepare a 16% solution (1:6 in water) of potassium platinum chloride -- Potassium Tetrachloroplatinate (II).
4. For an 8x10 print mix 12 drops of each solution thoroughly ( count all of the drops of each different solution into a shot glass and then swirl the liquid in the glass vigorously to form a single, combined, solution).  
5. Brush the truly mixed solution onto a sheet of paper such as Bergger Cot320, place it in a dark, damp location to "dry" enough that the sensiziter is no longer wet enough to damage your negative. Place in contact with a negative and expose to UV or sunlight. 

Richard Eugene Puckett's 2013 Platinotype Supreme formula:
1. Prepare a 20% solution of platinum chloride, from Potassium Tetrachloroplatinate (II). Store it in a properly labelled bottle, in a cool, dark locaiton, for at least 18 days before use.
2. Prepare 10ml of a 40% solution of Ammonium Ferric Oxalate (blue-gray tone) or of Sodium Ferric Oxalate (brown-gray tone).
3. Prepare a 2% solution of vitamin c, ascorbic acid (or sodium ascorbate), and count 8 drops of that 2% C solution into the 10ml bottle of ammonium ferric oxalate. Recap the ammonium ferric oxalate bottle and shake it vigorously for 30 seconds. 
4 For an 8x10 print mix 12 drops of each solution thoroughly ( count all of the drops of each different solution into a shot glass and then swirl the liquid in the glass vigorously to form a single, combined, solution).  If a given negative needs a contrast boost, prepare a simple solution of 26% ferric oxalate and use that without C added. A clearing bath in the standard 2% hydrochloric (muriatic) acid will suffice to dissolve the surfeit ferrous iron after print out is complete.
5. Add half as many drops of glycerin as of platinum chloride (such as, 6 drops of glycerin to 12 drops of platinum) and mix thoroughly.
6. Pour out and brush (or use a glass coating rod wrapped with flannel, as William Willis specified in 1878) evenly onto a sheet of paper. Appropriate papers include Legion Revere Platinum, Bergger Cot 320 (NOT 160), Hahnemuhle Platinum,etc. 
6. Allow the sensitized paper to dry in a dark place for usually 15 to 30 minutes. Do not stress if you forget about it for a few hours...
8.  Place the paper in contact with a negative and expose to UV or sunlight.

Robert Hunt's Manual of Photography, 5th Edition, 1857

Robert Hunt's manual is an invaluable resource with which (along with Google Books) anyone interested in 19th century photographic printing processes should become familiar. Certain persons have counted (with tremendous success) on the ignorance of contemporary photographers and printers to claim to have "invented" many tools and processes that were known to their counterparts 100 and more  years ago. The internet has only accelerated the plagiarism and widened the ignorance. 

Hunt's Manual of Photography, 1857 5th Edition is available free for online reading or download at https://archive.org/stream/manualofphotogra00hunt_0/manualofphotogra00hunt_0_djvu.txt Hunt, Manual of Photography in text format.