The Texas Chrysotype Revolution
The Texas Chrysotype
The Largest Chrysotype
The Electrumtype
The Kytheratype
The Manual
The Prints
The Videos
The Artist


After you dissolve 4 grams of ammonium ferric oxalate crystals in 8 ml of distilled water, top the solution off to 10 ml and pour it into a stopped brown bottle. Add ascorbic acid solution (1% for gold or 2% for palladium and/or platinum) to the bottle of 10ml of 40% ammonium ferric oxalate (or of sodium or lithium ferric oxalate). As I describe repeatedly in my videos and online articles, remember that you have to shake the bottle vigorously -- for 15 to 30 seconds -- to disperse the ferrous iron subsequently created evenly throughout the solution. Otherwise, the ferrous iron will simply precipitate out of solution and fall to the bottom of the bottle: you likely won't get satisfactory results when you attempt to print with a solution of AFFO in that state. I apologize to the general community, as I have been guilty of assuming everyone knows that when you add one chemical or compound to another when preparing a solution (for alt process printing) you generally shake or stir the admixture to get it into a proper solution. However, I encountered recently a rather unpleasant person in of all places the APUG forums who could not make a print in palladium because no one had ever explained this fundamental concept to him.

Ruthenium and Iridium:Sources

I have found the best prices for iridium and ruthenium to be had at ArtCraft Chemicals iridum and ruthenium in 5 gram units and Pressure Chemical Company Iridium by the gram and Ruthenium in 10 gram units. Read on to understand why I mention this. Purchase iridium(III) chloride hydrate and ruthenium(III) chloride hydrate. Dissolve directly in distilled water at 20% or less working strength for iridium and 10% or less for ruthenium.

RUTHENIUM: Final Results With Palladium Print Out And With Silver Nitrate Develop Out

Ruthenium is a member of the platinum metals group. Although ruthenium is extraordinarily rare, the price is relatively low, lower than palladium. Although ruthenium will not print out fully on its own, not even with a double ferric ferrous oxalate, it has three big applications for photographing printing:

  1. Ruthenium prints out really fast. Palladium, gold and/or platinum mixed with ruthenium print out really fast. I mean 15 to 90 seconds fast. This can be good, if you rely on sunlight for printing. It can be bad if you are used to prints requiring a certain amount of time as you will have to adjust to prints that are ready in a tenth the time you expect.
  2. Ruthenium alters the look of platinum, palladium and gold images by smoothing them to an almost unreal degree. For some, a palladium-ruthenium print is likely to look too smooth, too creamy, too perfect, like some digital thing over-Photoshopped.
  3. Ruthenium develops out beautifully in silver nitrate.
But first, a cautionary note about ruthenium. Now, ruthenium is definitely not as horrible as the dichromates. Accidentally ingest one gram of potassium dichromate and you may as well just sit down and write out your living will, because you're going to die very soon. As for ruthenium, the MSDS indicates that whereas the body can excrete gold, platinum, and palladium, it cannot remove ruthenium. As a result, intentional or accidental ingestion of ruthenium results in the metal being stored conveniently in the bones. The MSDS indicates bone cancer is believed to be the result of ruthenium stored in the bones. It doesn't say how much you would have to ingest but as the mass-murderer Mao wrote, a journey of a thousand miles begins with one step. In addition, ruthenium dust or solution is indicated to be a strong irritant even if not ingested, damaging mucous membranes and so on. Hence, do not use ruthenium if you cannot wear long rubber gloves (to prevent staining the skin and possible absorption especially through cuts or broken skin) and cannot wear a face mask to prevent accidental splashing of ruthenium powder or solution into your mouth, nasal passages or eyes. An accident can occur at any time through carelessness or distraction. Also note that the other chemicals used in these processes are also toxic and require care in handling, preparation and printing. This cautionary note includes AgNO3 (silver nitrate), ammonium ferric oxalate, chlorides of palladium and of iridium. While I don a face mask/respirator for mixing solutions (including dissolving all powders), I wear rubber gloves from the moment I finish tracing the outline of my negative on the paper to the time I hang up a wet print to dry. Even the clearing solutions merit respect (and gloves).

Prepare fresh ammonium ferric oxalate as for dry print out with palladium, as above with 8 drops 2% C added to the 10 ml 40% ammonium ferric oxalate IN THE BOTTLE. Shake the bottle for 30 seconds! You have 10ml AFFO(8:2%C). Label it.Altneratively, mix up a fresh solution of lithium ferric oxalate (or buy some from Bostick & Sullivan). (For Mr. Sullivan's lithium ferric oxalate formula, go here B&S Articles and scroll down to the All About Ferric Oxalate link and click that.) I mix my own from oxalic acid, ferric oxalate and lithium carbonate (which I bought at a local glass making/pottery place where middle-aged, middle-class women go to learn how to make pots). Pour 10 ml into a brown bottle and add 8 drops of 2% C and shake vigorously. The lithium ferric ferrous oxalate is considerably contrastier than ammonium ferric ferrous oxalate and so you need to add less contrast booster

Prepare a solution of ruthenium by dissolving 1 gram of ruthenium(III) chloride hydrate in 10 ml of warm water (~90 degrees Fahrenheit). Dilute some of the solution 1:1 with water. Note: Ruthenium is available from Artcraft and a few sellers on Ebay. General price is $27USD to $30USD per gram, typically with a 5 gram purchase. I bought 5 grams for $145 including shipping. It mixes up to 50 ml.

To mix with palladium, for a 4x5 print, add 3 drops of the AFFO(8:2%C) to a shot glass. Count 3 drops 15% potassium palladium chloride OR lithium palladium chloride into the shot glass. Dilute 1 drop of 10% Ru 1:1 w/H2O to make a 5% solution. Add 1 drop to the palladium and AFFO. Depending on your negative's contrast, you may need to add anywhere from 1 to 3 drops of 26% ferric oxalate (NO ascorbic acid added!), or ammonium dichromate or Bostick and Sullivans Na2 contrast booster. Use whatever works for you -- on hand, cheapest, most dangerous, whatever. If you use lithium ferric ferrous oxalate you probably won't need to add any ferric oxalate (or other contrast booster). Swirl to mix thoroughly. Brush onto a sheet of Revere Platinum, 140 or 300 gsm, or onto Arches Platine, Canson Colorline, or other Pd-friendly paper. Do not be concerned if any precipitated ruthenium particles are present: they will break down during drying and subsequent exposure to UV. Place in dark to dry completely (~15 minutes).

Expose paper, by inspection, in frame in contact with negative.Print out is very fast with ruthenium, much faster than with gold, platinum, or palladium. I obtained a 15 second print out, in sunlight, with an older (~3 months) bottle of AFFO(8:2%C), and a 90 second print out with a fresh solution. When print out is slightly lighter (~1/3rd to 1/2 stop than desired) remove print from frame and immerse in 10% citric acid if colorline or Revere 140 gsm, in very weak (.5%) hydrochloric (muriatic) acid if Platine or 300 gsm Revere Platinum. Then wash in running H2O and continue clearing as for palladium. A print made using process as described:

The above print was slightly warm (a golden honey tint to it) and the contrast was much softer when still damp. Almost surreal smoothness. To preserve at least something of that, of course coat in gelatin while still damp and then harden with chrome alum.

Ruthenium developed out with silver

Prepare AFFO and ruthenium as above. Prepare a 4% solution of silver nitrate. Tip: water must be very warm but not hot. If the AgNO3 is cloudy, you can very gently warm while stirring to clear. A little cloudiness is acceptable (but not ideal). For a 4x5 (4x volumes for an 8x10), mix 1 drop 10% ruthenium with 5 drops AFFO(8:2%C). Brush onto paper as above, for Pd-Ru. Again, ignore any particulates: they vanish with no trace.Dry in dark place and expose to UV in frame in contact with negative.

Print finishes very quickly! Print is ready when faint image is visible. Similar to develop out palladium. (Test strips are always a good idea until you nail down your technique.) When print is ready, remove from frame and place in a flat-bottom tray (no ribs!!!). Optionally, mix just 4 ml 4% AgNO3 with 4ml regular super market corn syrup to thicken and make handling easier. Put on long rubber gloves! With a brush or puddle pusher in one hand, pour the AgNO3 outside the image area (do not splatter any!) and very quickly brush/push it evenly across the image. Development is instantaneous! You are warned. Notice the splatter spots on my test print, below, which resulted from pouring out the AgNO3 from about 2 inches above the paper. The vessel containing the AgNO3 should be held only a few millimeters above the paper when pouring. I was in a hurry.

Clearing is first bath in cold H2O for 2 minutes, then soak for 10 minutes in 10% tetrasodium EDTA. Then wash in running H2O 5 minutes. Then fix. Mix fixer 1 part fixer to 20 parts H2O. So, to cover a print in an 8x10 tray, add 10 ml stock strength fixer to 200 ml H2O. If the print is too dark, you can mix instead 1 part fixer with 3 parts water (i.e., in this case, 50 ml fixer w/ 150ml H2O). The fixer will lighten the print if this strong. Keep water running nearby to stop fix bleaching right away if necessary. Fix for 4 minutes max (unless bleaching). After fixing, wash in running H2O for 5 minutes, then soak in standard Hypo Clear (sodium sulfite) one-shot solution as for silver gelatin prints. Final wash 30 minutes for 140 gsm Revere Platinum or Canson Colorline, 45 to 60 minutes for Arches Platine or Revere Platinum 300 gsm. Feel free to test other papers. Gelatin sized papers should work, as well as baryta papers (if sensitized, fix and clear to remove silver, of course). Final image should be an almost unreal creamy smooth. Print will sharpen and lose some of the extreme smoothness on dry down. Coat still damp print in gelatin and harden with chrome alum if you wish to preserve the damp look. This is a very rough, cell phone camera version of a 4x5 contact, spotted slightly for some splatter and with too much unsharp mask applied -- the contrast was too soft for the cell phone camera to record the detail adequately:

This print was still damp. On dry down it will turn from sepia to brown.


Iridium is a noble metal of the platinum family. The master printer and photographer Irving Penn frequently mixed iridium with platinum and with palladium for his prints. Based on my results with iridium, I suspect Penn's motivation was to nudge print color toward neutral gray scale and also to deepen the Dmax of his prints. Warning: read the MSDS on iridium and take proper precaution with this metal.

This contact print, on Revere Platinum 140 gsm paper, illustrates the value of iridium as an additive to palladium (or platinum, or gold). The formula was 3 drops of ammonium ferric ferrous oxalate (8 drops 2% C added to a bottle containing 10ml of 40% ammonium ferric oxlate), 2 drops of 26% ferric oxalate (no C added), 3 drops 15% lithium palladium (potassium palladium would work equally well), and 1 drop 5% iridium. The image printed out fully at normal speed (~5 minutes in my 6 13w UV bulb box). It looks like a platinum print with a contrast boost more than palladium. Notice the amazing black of the model's eyes -- that is faithful to the original print.

As this 4x5 contact print shows, iridium is a vigorous medium. It also exhibits slight grain, more so than platinum (at least than the virtually grainless platinum obtained with my Fannintype, in which I use glycerin to constrain the grain). This image was made by mixing 2 drops of 10% iridium with 1 drop of 15% palladium. The sensitizer was 3 drops of ammonium ferric ferrous oxalate, of course, prepared with 8 drops of 2% C. An additional 2 drops of 26% ferric oxalate (no C) boosted the contrast nicely. Clearing was citric acid, water, t-edta, water, t-edta and a final wash. Paper was Bergger Cot 320 sized with gelatin.

I have previously developed out iridium with silver nitrate. The image was strong and vigorous as this one. Because of the grain, however, I expect to keep my use of iridium with palladium, platinum, and gold down to about 25% maximum of total metal solution. Tip: Ruthenium will smooth over any roughness or grain induced by iridium.