i was doing research and was wondering why the fluorescent fixtures of the past had that weird greenish glow to them and today they are "perfect"— but lack the same "mood" the original ones did.

i found out that fluorescent tubes used halophosphate until the 70s and 80s, and then they started making triphosphor tubes. now the most common ones i see are multiphosphor tubes, and halophosphate tubes are just impossible to find.

does anyone know if the original halophosphate tubes are still available anywhere? the 4100K and higher lamps especially had this quality to them that is just so unique.

Assuming you are in North America, Warm White (3000K), Cool White (4100K), and Daylight (6500K) are still widely available, though not in the popular 4' 40-watt and 8' 75-watt T12 sizes, except for this F40CW in a shatter-shield format. You can even still get a White (3500K) F8T5 here, an F34T12 here, and an F15T8 here. For a really pronounced greenish color, you could try Cool Green, which was somewhat common at one time but has pretty much vanished.

The thing is, the halophosphate can not offer higher CRI, nor higher efficacy.
So those lamps can not pass the efficacu standards imposed in last few years: The tube has to have high efficacy, with the exceptions of when the color quality is above certain limit. And neither of them could be fulfilled by the halophosphates.

The cool green was used in the earlier days as a way to get maximum efficacy (the peak output of the phosphor matched the peak eye sensitivity). It disappeared when the "cool white" mix became of similar efficacy, but as it offered better color, I guess it was the pure market pressure (at that time), what pushed the greenish types out.
Now with the competition of the tri-phosphors (where you get both higher efficacy, as well as better color rendering at the same time) there is no way it will come back. Maybe except as a decoration, but that would be with way lower power and light intensities (and most likely made of LED's).

Halophosphors can produce high CRI at a grave expense of efficiency especially at lower color temperatures. Examples of high CRI halophosphor lamps are GE Chroma 50 (5000k, 90 CRI), Sylvania Incandescent Fluorescent (2700k, 89 CRI) and I think the cool white supreme is either halophosphor based or a mix of triphosphor and halophosphors.

I didn't know Incandescent Fluorescent was 89 CRI. Sounds like an improved version of the GE Reveal fluorescents. I'd love to see the color come back, but I think progress has stalled on fluorescent lighting. This could turn into a whole other discussion, but I think we've reached the beginning of the end of the fluorescent light, sadly.

Halophosphors can produce high CRI at a grave expense of efficiency especially at lower color temperatures. Examples of high CRI halophosphor lamps are GE Chroma 50 (5000k, 90 CRI), Sylvania Incandescent Fluorescent (2700k, 89 CRI) and I think the cool white supreme is either halophosphor based or a mix of triphosphor and halophosphors.

Yes, but the expense is rather ridiculous - the efficacy is then around 30lm/W even on rather large lamp, with ballast losses you are at about 20..25lm/W, not much advantage over real incandescents with CRI 100...
I would guess this was the prime reason, why they didn't survived on the market...

Best crappy light (what a weird name  ) memory from the past is all those small general stores and companys which were lit by random combination of halophosphate lamps. My favorite is combination 530 + 740. It was always nice to try find the dimmest (and thus probably oldest) lamp cause most of them did not do mass replacements.

new fluorescent lamps are kind of boring in that sense that there is very little difference between manufacturers IMO. Everything has been standartized so well. eg. 840 from Osram is almost identical to compared 840 from Philips.

My favorite is combination 530 + 740.

That was for lousy amateurs and dilettantes. Professionals mixed in 765, too!

most of them did not do mass replacements

Some months ago I wanted to look back after such a professional installation but had to discover that all tubes had been replaced by new 840 ones

I always liked "mixed up" fluorescent lamps for that unique aura you get but you usually only see that in smaller installations.
I do agree, though, older lamps had a unique "feel" to their light quality.