UV light destroys DNA bonding. It’s why we get skin cancer. It destroys the cells ability to regulate cell growth because the DNA sequences that regulates it become corrupted at the bonding level.

So there goes your DNA evidence if you expose it to UV light.

Probably no other pieces of evidence have put through so many different processes through the decades than the Zodiac letters.

These diamonds are something I brought up on Reddit a long time ago to see if they had an explanation there. None were given.

Speculation:
I am a biologist with a background in biochemistry. If I was to guess these diamond patterns are probably part of some forensic test something else went through. A swabbing maybe that left staining. One possibility is that the envelope seals were tested for saliva.

Secretion status has been known to science for over a century because of early blood work done as obviously that stuff is important for us humans. In the 60s they could learn blood type from secretion status testing or if a suspect was a secretor or not. Here secretor means their saliva leaves anti-bodies but if there are no anti-bodies they are a non-secretor and only a small % of the population are that so it’s good to find it. Anyway Zodiac being forensically aware probably didn’t lick the envelopes. So really there was every reason to expect he didn’t lick the stamps either. Back in the 60s the Zodiac was not forensically aware of DNA but he was of secretion status. That’s a good reason why no saliva DNA would be found.

Anyway whoever tested the envelope seals probably left chemical residue on them after the swabbing and then the letters were put back into the tested envelope and the residue stained them creating the diamond patterns when taken back out again. That’s my guess.

I am a biologist with a background in biochemistry. If I was to guess these diamond patterns are probably part of some forensic test something else went through. A swabbing maybe that left staining.

Well, that burst the bubble, but sounds reasonable. I’d thought it might have something to do with processing the letters for evidence, but was starting to feel a bit of hope that it was something new

I suppose there’s still a possibility of it being something, but it helps knowing there’s a good explanation.

As far as the ultraviolet and radiograph tests that OP mentioned, maybe they could do just a page or two? It sounds like it would have a lot of potential… then again, I suppose if that’s the case it may already have been done.

I am a biologist with a background in biochemistry. If I was to guess these diamond patterns are probably part of some forensic test something else went through. A swabbing maybe that left staining.

Well, that burst the bubble, but sounds reasonable. I’d thought it might have something to do with processing the letters for evidence, but was starting to feel a bit of hope that it was something new

I suppose there’s still a possibility of it being something, but it helps knowing there’s a good explanation.

As far as the ultraviolet and radiograph tests that OP mentioned, maybe they could do just a page or two? It sounds like it would have a lot of potential… then again, I suppose if that’s the case it may already have been done.

looking at anything but the original would be like looking at a friends X ray to see if your arm is broken

looking at anything but the original would be like looking at a friends X ray to see if your arm is broken

True, but I don’t think anyone had suggested that. Still, good point.

I’m going to continue looking for ways LE might have swabbed the surface of the letters, and see if that really is a thing. The fact that they’re all diamond shaped, and in roughly the same position makes me think they might have been batch tested by the same person or lab. I’m still Googling for tests they might have done. I believe the pencil marks on some of the pages are the locations of finger and palm prints, so it wouldn’t surprise me if they’d done something as destructive as swabbing the entire letters. Although, that gives hope that OP’s UV/radiographic tests could still be done.

I’m going to continue looking for ways LE might have swabbed the surface of the letters, and see if that really is a thing. The fact that they’re all diamond shaped, and in roughly the same position makes me think they might have been batch tested by the same person or lab. I’m still Googling for tests they might have done. I believe the pencil marks on some of the pages are the locations of finger and palm prints, so it wouldn’t surprise me if they’d done something as destructive as swabbing the entire letters. Although, that gives hope that OP’s UV/radiographic tests could still be done.

Basically it is the V shape that resembles an envelope’s seal IMO. You know the flap on the back? So if you test those areas and then put the letters back inside, the chemicals applied to the flaps can penetrates through the layers of paper inside creating a V or several Vs if the letters are little loose inside. My guess is that what we are seeing here are several attempts to do things with envelopes and the letters put back inside the envelopes again instead of kept separate from them after. We are seeing 50 years of attempts at recovery and 50 years of all the problems with those methods appearing which wouldn’t happen today.

The fact is that older methods often destroyed evidence even during the 80s and 90s. UV light destroying DNA bonds and the fact we needed a somewhat large sample size to work with which gets destroyed in the process meaning the forensic expert on the stand had to admit the DNA evidence they used up to get a profile is no longer there because it is destroyed by the process. Evidence gone basically. That is what PCR changed and touch DNA. It takes a single strand and them multiplies it in copies so the sample size increases and you don’t end up using all the evidence. That is why it works with such small pieces of possible genetic evidence. It can even lift DNA from people who made clothes in a shop that haven’t been washed for example. Very sensitive stuff and in some cases found serial killers which never existed. https://en.wikipedia.org/wiki/Phantom_of_Heilbronn

Basically it is the V shape that resembles an envelope’s seal IMO. You know the flap on the back?

I totally get what you’re saying and it’s a good observation. Also great point that these have been examined and re-examined hundreds of times over the decades. I still think some of the letters look like they’ve been physically swabbed or painted with something, though, and several have vertical lines running right down the center of the page. Idk, it’s hard to parse most of what we see without having access to the people who did the original work, and I don’t generally get my hopes up for anything people might find on the Internet, but I think at this point, I would like a definite answer on what the marks are. Also the fact that the paper has browned with age, but the lines haven’t, could mean whatever caused them was done ages ago, so if it is from a forensic test, hoping to find some mention of it being used in the 70s or 80s.

The fact is that older methods often destroyed evidence even during the 80s and 90s.

It’s really unfortunate that older methods were potentially so destructive. I guess at the very least, it might mean that most of the DNA evidence is already lost, so using a bit more UV might not be a bad thing.

I’m in the camp that Zodiac was a math nerd, and into brain teasers and puzzles in his personal life. I was the same way as a kid, and would make puzzle books with friends, and then we’d all try to solve what the others had created. I sort of see Z as being the same type of person, so when I get the bug, I’m usually looking for hints that he’s hidden information in his letters and cyphers, and the diamonds are sill really interesting. I am sort of leaning towards them being forensic related at this point though.

I would suggest looking at the Exorcist communication. It appears to me the Zodiac was working on it and then crumpled up the note and threw it away, went back to retrieve it, looked it over again and added the symbols at the bottom after doing something with it. My belief is that the folding reminded him of using folds in some way with a puzzle.

For example the dot in the bottom left seems to intersect with two folds like the center of a X.

This is why I am very interested in PIN HOLES in all the documents included the maps. Did the Zodiac make them or LE. That answer can be critical to discovering Zodiac’s engineering mechanisms behind any puzzle designs. Pinning down stuff.

Also you might be into this viewtopic.php?f=70&t=4907

This is why I am very interested in PIN HOLES in all the documents included the maps. Did the Zodiac make them or LE. That answer can be critical to discovering Zodiac’s engineering mechanisms behind any puzzle designs. Pinning down stuff.

IMO, If the pin holes came from Zodiac, LE, or both., they were most likely for the same purpose, and that’s to simply pin the letter to a board or wall. I don’t personally think the holes have any meaning.

I have also manipulated the letters in Photoshop in the past and noticed the diamond shapes. Ive always attributed those to the folding of the letters and being stored in an envelope for "x" amount of time. It looks like the envelope did something to the letters.

Would still like to use X-Ray and PMI on the letters, but even if I had the letters, I dont have access to the technology anymore. Layed off because of the virus.

I did take a quick trip down to SoCal and drove through San Francisco on my way about 7 weeks back north. I re-visted the Lake Herman Road site, Blue Rock Springs, Lake Berryessa site, and what I thought was Paul Stines site. I also tried to located the Domingos and Edwards site on 101 on my way back north, but was unable to. When I stop at these places, I just get this feeling like none of this will ever be solved. Plus, there are Zodiac symbols written in sharpie at some of them, and while this certainly work as identifiers to know your in the right spot, it also feels disrespectful, then I feel like Im being disrespectful for even going there.

I’d always assumed this was something well known, but I haven’t been able to find any other posts about the diamond patterns, so I’m just going to upload a few more examples. If anyone has any thoughts, I’d really like to hear them.

These were chosen randomly from some of the color scans I’ve been able to collect. The diamond pattern shows up on roughly 80-90% (edit: going through the letters, and I guess it’s more like 50-60%) of the letters, including the Phillips map posted above.

These are scans. Maybe the diamonds are artifacts of the scanning process, rather anything Zodiac did. So for instance, the light source inside the scanner may have been diamond-shaped.

I’d always assumed this was something well known, but I haven’t been able to find any other posts about the diamond patterns, so I’m just going to upload a few more examples. If anyone has any thoughts, I’d really like to hear them.

These were chosen randomly from some of the color scans I’ve been able to collect. The diamond pattern shows up on roughly 80-90% (edit: going through the letters, and I guess it’s more like 50-60%) of the letters, including the Phillips map posted above.

These are scans. Maybe the diamonds are artifacts of the scanning process, rather anything Zodiac did. So for instance, the light source inside the scanner may have been diamond-shaped.

I think I see Dr.D in there?…

No, my mistake…just paraedolia.

Hi.

Newbie alert.

Fascinating thread.

I see some people mentioned they think a chemical testing process occured with the envelopes that must have damaged the documents when placed back inside the envelopes. I think that is rational. Except look at the folds of the paper. The diamond marks do not tally with the paper folds. If you fold a piece of paper and then put it in the enevelope, it stands to reason any envelope damage would follow the folds of the paper. I don’t see this as damage connected to the envelope.

It can still be some kind of chemical testing process left behind on the paper, but would someone not have found such a forensic test of that time that matches this by now? I am not aware such a forensic test has been discovered.

Which if is the case, we have oursleves a clue.

Regards,

Ero

Hi.

Newbie alert.

Fascinating thread.

I see some people mentioned they think a chemical testing process occured with the envelopes that must have damaged the documents when placed back inside the envelopes. I think that is rational. Except look at the folds of the paper. The diamond marks do not tally with the paper folds. If you fold a piece of paper and then put it in the enevelope, it stands to reason any envelope damage would follow the folds of the paper. I don’t see this as damage connected to the envelope.

It can still be some kind of chemical testing process left behind on the paper, but would someone not have found such a forensic test of that time that matches this by now? I am not aware such a forensic test has been discovered.

Which if is the case, we have oursleves a clue.

Regards,

Ero

I still feel like there is evidence being overlooked in the letters….maybe something we don’t know how detect yet….