Silver bearing films

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goldsilverpro

In Remembrance
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I made this post, recently, on another forum. I have made several posts on this subject before but, since there is a little extra info here, I thought I would re-post it. Sorry for the redundancy. If I think of any other things, I will just add them to this same post. If anyone is interested in this subject, I would suggest re-reading this post occasionally.

Everything you ever wanted to know about film scrap.

The values:

Below is a quite accurate list of film values, based on the recovery figures of millions of pounds of film scrap, of the number of troy oz of silver per pound of film. These are US values. In my experience, some of the x-ray material might run higher in 3rd world countries. This may be due to their continued usage of some of the older types of film. In the US, the processing of film scrap is a dying business, since most all users are going digital. In many 3rd world countries, however, I would imagine that film is still widely used, since new digital equipment is expensive and they already have the equipment needed for the older technology.

The values given in the chart below are average values. They can vary considerably. For example, chest shots (less black) usually run lower. In general, the blacker the film (except for Dryview), the higher the silver. The names given are those used in the trade. BMX, CMX, and NMX were names given to those types at that time (probably in 1979-1980), but they stuck and are still used today. There are other types (circuit board litho, e.g.), but those listed probably make up about 99% of what's available. Most medical x-ray shots have dates on them. I know some of the Litho numbers don't seem to make sense, but they are the base of what are used by people in the trade. Litho (lithographic) film is used primarily in the printing industry - newpapers, books, etc.

You will receive on the average of about 60% - 70% of these values, depending mainly on volume and quality, when selling your film to a film processor in the US. Since these values are pretty much set in stone, the experienced film processor (or, buyer) can easily look at the film and know the approximate silver content. Therefore, you should get paid on the spot. If the processor wants you to wait and get paid on recovery, I would probably look for another processor. In most areas where there are no film processors, there are usually middle-men who buy film, accumulate it, and then ship it to a processor. They will offer much less than a processor. Everyone has to made a buck and shipping is expensive. There are only a hand full of actual film processors left in the US.

Notes on some of the film types:

"Dryview" is a Kodak trademark for their brand of x-ray film that is developed by heat rather by chemicals. Other companies besides Kodak also make this type film and the term, "Dryview", is used generically in the trade to represent all films of this type. Since no silver is removed during developing, virgin Dryview contains the same amount of silver as developed Dryview. Developed Dryview looks like regular film, whereas virgin Dryview appears as a sheet of completely clear (usually blue) plastic. Dryview can be distinguished by briefly holding a cigarette lighter under a clear (non-black) area - it only takes a second or two. If the heated spot turns black, it is Dryview. Dryview is more difficult to strip chemically than regular x-rays. Some processors won't buy Dryview due to processing difficulties. At the present time, in the US, I would guess that the majority of all new medical x-ray film scrap available is of the Dryview variety.

Dark room scraps (DRS) are just what is says. They are sheets of film that were scrapped, for various reasons, by the x-ray technician. When the DRS is of the rare earth variety, it should most always include all 3 of these types: developed x-rays; virgin x-ray material: and clear sheets of plastic. If there is no virgin material in the scraps, it is worth less. Sometimes, they pull out the virgin sheets and sell them separately. Virgin, or green, rare earth medical (and virgin Industrial) x-ray sheets are a solid light green color. However, when exposed to light, they turn purple. Virgin litho film is produced in several different solid colors and it also turns purple when exposed to light.

"Goldenrod" is a term used in the trade to designate litho film that has a sheet of yellow-orange paper attached to it with red (usually) vinyl tape. The paper and as much tape as possible must be separated by hand before the film can be processed. "Shucks" are x-ray films enclosed in paper envelopes along with the patient's paperwork for that particular x-ray. Here again, labor is required to separate the film from the paper. Due to the labor required to prepare both of these for processing and, because the paper and tape contribute significantly to the weight, both "Goldenrod" and "Shucks" are worth much less per pound. Also, since the "Shucks" contain personal information about the patient, fairly recent privacy laws require the processor to spend money to secure the facility from outsiders and to properly dispose of the papers containing this information. After stripping the silver, the PET plastic, itself, can be sold. However, since the vinyl red tape on Goldenrod is impossible to remove completely, it contaminates the PET plastic and makes it worth much less.

Although you don't see it often, the old high silver content "acetate" film listed below can usually be recognized by it's vinegar smell. Also, it often tends to crumble and the emulsion is sometimes wrinkled and falling off. It usually has the words, "safety film" imprinted on the edge of the sheet. The reason it is called "safety film" is that it replaced "nitrate film", which could become explosive when aged. Most movies before about 1955 (I think), are on reels of nitrate film. Many were lost because the film decomposed. Some are stored in large warehouses that are climate controlled.

The 4 and 7 mil thicknesses of litho film are .004" and .007" thick. These types are easily distinguished with a micrometer.

I didn't list dental x-ray film because it is so small that it takes many, many pieces to equal a pound and the weight generated by even a large dentist office or dental lab is very small. I don't know if anyone is trying to collect it or not. It would probably be a wasted effort, profit-wise. In the millions of pounds of film I have seen processed, I never saw a lot of dental x-rays. I would imagine that the silver content of dental x-ray scrap is about the same as the rare earth medical x-ray film listed in the chart below.

Medical X-ray Film:

Acetate - 1962 and earlier ------------------------------------- 0.25 tr.oz. Ag/pound of film
BMX (Before Medical X-rays – 1962 to 1976 ------------------ 0.235 tr.oz./pound
CMX (Current Medical X-ray) – 1977 to 1979 ----------------- 0.205 tr.oz./pound
NMX (New Medical X-ray) – 1980 to 1985 --------------------- 0.17 tr.oz./pound
RE (Rare Earth) – 1985 to Present ---------------------------- 0.10 tr.oz./pound
DryView - about 1996 to Present ------------------------------ 0.04 to .10 tr.oz./pound
Rare Earth DRS (Dark Room Scraps) – 1985 to Present ----- 0.04 to .11 tr.oz./pound
Cat Scans -------------------------------------------------------- 0.10 tr.oz./pound
GMX (Green - Rare Earth) - average undeveloped ----------- 0.18 tr.oz./pound

Litho Film:

News Litho – 4 mil film thickness – 95% black ---------------- 0.24 tr.oz./pound
A Litho – 4 mil – 85% black -------------------------------------- 0.20 tr.oz./pound
B Litho – 4 mil – 75% black -------------------------------------- 0.17 tr.oz./pound
C Litho – 4 mil – 65% black -------------------------------------- 0.11 tr.oz./pound
Z Litho – 4 mil – 50% black, or less – average value ---------- 0.08 tr.oz./pound
Virgin (undeveloped) Litho - 4 mil ----------------------------- 0.28 tr.oz./pound

News Litho – 7 mil – 95% black ---------------------------------- 0.13 tr.oz./pound
A Litho – 7 mil – 85% black --------------------------------------- 0.11 tr.oz./pound
B Litho – 7 mil – 75% black --------------------------------------- 0.08 tr.oz./pound
C Litho – 7 mil – 65% black --------------------------------------- 0.05 tr.oz./pound
Z Litho – 7 mil – 50% black, or less – average value ----------- 0.03 tr.oz./pound
Virgin Litho – 7 mil ------------------------------------------------ 0.15 tr.oz./pound

Industrial X-ray Film:

Black Industrial X-ray – average values ------------------------- 0.22 to 0.32 tr.oz./pound
Green (undeveloped) Industrial ---------------------------------- 0.65 tr.oz/pound max.

Miscellaneous Film:

Virgin 35mm Film Ends from photo processors (color) -------- 0.53 tr.oz./pound
Micro Film ---------------------------------------------------------- 0.08 tr.oz./pound
Micro Fiche --------------------------------------------------------- 0.08 tr.oz./pound
 
DryView films are easily cleaned adding some ethyl alcohol to the sodium hydroxide solution and heating to the usual temperature.

Silver behenate is the heat sensitive compound used in new technologies like DryView and CTP...silver can be recovered from digital technology developers but it is in a colloidal form.I am working on it and I will post my research soon.

GSP,my Dear friend:

I am very happy that you finally posted the list in which we discussed a lot for some time.

Have a nice day.

Your friend:
Manuel
 
Manuel,

I am very happy that you finally posted the list in which we discussed a lot for some time.
I actually posted it quite awhile ago on that original thread.

DryView films are easily cleaned adding some ethyl alcohol to the sodium hydroxide solution and heating to the usual temperature.
We had no problems stripping it with the standard sodium hydroxide plus some proprietary additives. The problem is that, if you want to sell the PET for top dollar, you have to remove 100% of the Dryview film from the PET. If you don't, there will be black flakes contaminating the plastic and it's value will be far less (or, zero). Also, on some types of film, there is a thin transparent coating of mylar on the PET. This also must be removed in order to get full value for the PET. Here again, we used some proprietary additives.

silver can be recovered from digital technology developers but it is in a colloidal form.I am working on it and I will post my research soon.

Very interesting. I look forward to your posts.

Chris
 
Two questions:

1) I have three large garbage bags of microfiche film strip that a medical waste company delivered to me a while back (amongst other electronic scrap). I believe they contain patient records or something, but I haven't bothered to look, because I don't care. If they do contain records then the medical waste company really screwed up, but I am looking the other way, and since I plan to destroy it one way or another, it doesn't matter. Question is: does this have any silver content?

2) I recently acquired a box that contains 28 packages of 50 sheets each of undeveloped 8x10 photographic film. The description that came along with the box says, "Photomechanical film type, plastic material, black & white emulsion type, reproduction type-positive, emulsion sensitivity - artificial light, clear base color". I'm a complete and total neophyte when it comes to photographic film so would appreciate any insight as to what I have here. Perhaps it's more valuable to an old-school photography buff that still likes to develop photos traditionally?

Thanks!
 
Chumbawamba:

Sorry,I am late because at this moment I am busy with my photo bussines,scholls go to vacation on July 9th so I am working hard.

First thing you have to do is checking if your film is silver halide or DryView type...get some CLOROX,dip a piece of film...if the film gets clean then it is silver halide type then you can process it with NaOH process,FeCl3 process or oxalic acid process.If the film does not get cleaned then it is DryView type so you can process it with NaOH and some additives,like ethyl alcohol.

If the film is not exposed and it is silver halide type then you can process it with thiosulphate process.

I hope it helps.

Regards.

Manuel
 
I wish I had known about this years ago. I have been in the printing business for the last 30 years. And in that time I have literally seen tons of litho film. But, for the last 6-8 years we no longer use film. Everything is now done by computers directly to the aluminum printing plate. (and no I can't get those plates, the owner is wise to their recycle value)

One place I worked at had a camera that you could walk into. It held a sheet of film 28 x 40 or larger.
 
cyberdan said:
I wish I had known about this years ago. I have been in the printing business for the last 30 years. And in that time I have literally seen tons of litho film. But, for the last 6-8 years we no longer use film. Everything is now done by computers directly to the aluminum printing plate. (and no I can't get those plates, the owner is wise to their recycle value)

One place I worked at had a camera that you could walk into. It held a sheet of film 28 x 40 or larger.

I'm surprised the owners weren't aware of the scrap value of the litho film. Itinerant film buyers have been going around, hitting every printer, newspaper, hospital, etc., for many years. They didn't pay much but they did pay something.

IC manufacturing facilities have huge reducing cameras that reduce large artwork (say, 48" x 48") down to the size of an IC chip. The biggest one I saw had a long bellows and weighed several tons. It was mounted on rails on the ceiling.
 
goldsilverpro said:
I'm surprised the owners weren't aware of the scrap value of the litho film.
They probably were, I just wasn't. I know there was a special bin all old film went into and there was some kind of filter in the developing bath that got changed but not thrown out. (probably full of silver sludge?)
 
cyberdan said:
goldsilverpro said:
I'm surprised the owners weren't aware of the scrap value of the litho film.
They probably were, I just wasn't. I know there was a special bin all old film went into and there was some kind of filter in the developing bath that got changed but not thrown out. (probably full of silver sludge?)



I used to work for Heidelberg on prepress equipment. Platesetters, imagesetters, processors, scanners, and so on. Customers generally had a deal with a local company that supplied an electrolytic silver recovery unit to make the rinse water going down the drain compliant with local laws. Someone would go onsite periodically to clean the silver out of the recovery unit. I presume besides use of the equipment the printing company also got some cash for the silver?

macfixer01
 
macfixer01 said:
cyberdan said:
goldsilverpro said:
I'm surprised the owners weren't aware of the scrap value of the litho film.
They probably were, I just wasn't. I know there was a special bin all old film went into and there was some kind of filter in the developing bath that got changed but not thrown out. (probably full of silver sludge?)



I used to work for Heidelberg on prepress equipment. Platesetters, imagesetters, processors, scanners, and so on. Customers generally had a deal with a local company that supplied an electrolytic silver recovery unit to make the rinse water going down the drain compliant with local laws. Someone would go onsite periodically to clean the silver out of the recovery unit. I presume besides use of the equipment the printing company also got some cash for the silver?

macfixer01

I have two of these units and we still use film in the program I teach in.
When I get back from holidays I will be recovering silver
 

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