So i went back to the thrift shop and got the TL-Mini Osram 13w 630 "Furniture White".

Again, it seems like a mixture between some of the triphosphor phosphors (the teal and the orange-red-deep red) and a bog standard halophosphate mixture. I still am wondering why they would do such things. The 630 color nomenclature suggests a bad CRI. But why bother mixing in the expensive phosphors if it's gonna be meh anyway?
Either way, it looks very similar to the Crompton "Halophopsphate" tubes spectrum wise that i wrote about earlier. I need to try out different software - one that makes it more obvious when things clip.

The color seems quite alright by the way.

Coincidentally, i found another 'Furniture White' lamp in the recycling bin at the hardware store. Didn't take it with me - simply no space. But it's extremely rare, that's for sure.

Thanks for indulging some hoarding and publishing a spectrum of this Filling the gaps in a classic rare earth spectrum likely makes color perception better, even if if overall CRI score the lamp gets is mediocre. Also, may look like an upgrade for home users habituated to '530 color. And by using half-halo mix Osram probably saved a little bit of cost, for a very price sensitive end-user home market, where even 0.5EUR for a luminaire matters.

The Americans have tubes with triphosphors and halophospate blends, and produces 70% CRI.

I need to figure out what the efficiency of the lamp is. Because one reason for the deprecation of halophopshate lamps, was the lower efficiency than triphosphor. I'm thinking that this may be a way to scoot the halophosphate just past the efficiency regulations.
But since it's a rare lamp, it's not easy to find such data. Nor do i know the power and efficiency thresholds of the early 2000s regulations on fluorescent lamp efficiency.

A wild guess it will be approximately in the middle between efficiencies of T5 13W 827 tube and the same tube, but in halo 640 or 530.

I guess this colour was widely used for IKEA furniture and cup board lighting? Quite possible that IKEA wanted their own distinctive warm white colour blend. I’ve seen these tubes mainly in IKEA kitchen in the early 2000s.

That’s a most unusual spectrum for a fluorescent lamp, which I have only come across before in the short-lived Sylvania Luxline Elite series lamps of the 1980s.  Also extremely rare, they had a dual coating with a very thin layer of triphosphor applied to a base coat of halophosphor.  In those days it was done for cost saving - tri lamps cost at least twice as much to produce aa halo and not all customers would pay the higher prices, so an intermediate level was produced.  It hardly sold either, and was soon withdrawn.  Apparently customers were either interested in colour rendering and would pay for the best, or they were not interested at all and wouldn’t pay a penny more for something slightly better.

Anyway, does the spectrum image imply that you have your own spectrometer?  If yes, can you calculate the precise CRI and CCT of this unusual lamp?  If you also have standard Halo and Tri tubes, you could measure all three, and calculate the relative lux values for each if you measure all eg at the centre of the tube and at fixed distance to your spectrometer.  That would be interesting to see how the relative efficacies compare.

Aha, interesting! It surprises me that the triphosphor blend is that expensive. I have never felt that triphosphor lamps were that expensive for the amount of light (and honestly, the sheer size!) of what you're getting. Anything between 8 and 16 euro for a Philips one, with not much difference between a 640 and an 827 tube (The two most common ones). I'll see if i can find a shop catalog from the pre-LED days and see if there's much retail price difference.

For intensity measurements i'll just take the lux meter from work. The Little Garden spectrometer is webcam based, so the absolute intensity measurements may not be possible, depending on whether i can turn off the auto gain control.
A friend is gonna give me a 13w 827 tube, i can compare it with that one. I can also source an 13w 640 tube, but will the difference in color temperature influence the lux measurement?

That’s a most unusual spectrum for a fluorescent lamp, which I have only come across before in the short-lived Sylvania Luxline Elite series lamps of the 1980s.  Also extremely rare, they had a dual coating with a very thin layer of triphosphor applied to a base coat of halophosphor.  In those days it was done for cost saving - tri lamps cost at least twice as much to produce aa halo and not all customers would pay the higher prices, so an intermediate level was produced.  It hardly sold either, and was soon withdrawn.  Apparently customers were either interested in colour rendering and would pay for the best, or they were not interested at all and wouldn’t pay a penny more for something slightly better.

Anyway, does the spectrum image imply that you have your own spectrometer?  If yes, can you calculate the precise CRI and CCT of this unusual lamp?  If you also have standard Halo and Tri tubes, you could measure all three, and calculate the relative lux values for each if you measure all eg at the centre of the tube and at fixed distance to your spectrometer.  That would be interesting to see how the relative efficacies compare.

would Thorn's Pluswhite (736 in modern colour code parlance) not have a similar spectrum also? as I understand it, that colour from Thorn was also a similar attempt to create a middle of road tube, mainly halophosphate but with a thin coating of Triphosphor to boost things a little

I have also read that in the US the SP30 SP35 SP41aka 700 series of fluorescent tubes are also a combination Halo and Tri tubes, I have some of these myself, but not yet any sort of spectrometer to check em with https://www.lighting-gallery.net/gallery/displayimage.php?pos=-223812

and it might be worth checking the spectrum of the F14T12/KB tube I gave you, I have also suspected those of being a dual-coat tube as GE only give them a CRI of 70 but i know they do contain blue rare earth phosphors at least

Someone gave me an f14t12 but i'm pretty sure it wasn't you - i picked it up at the house of a Dutch person.

AFAIK that one is standard cool white. I'm almost at the point of being able to easily fire it up - i need to source an extra 20w ballast from the scrapper.

I do have some 740 tubes too. But those are purely halophosphate. Osram color code 25, 'Universal white'. So oddly, better color rendering than the furniture white 'mixed' tube, though i much prefer the warm white of the 630 furniture white.

For those who want to buy one - including fixture - i found some for sale right here: https://www.hollandlamp.nl/hera-plafond-wandarmatuur-fd-44-lamptype-tl-buis-d-16mm-13w-4051268060882.html

Smaller 6w 630 lamps are here: https://www.lamp.nu/contents/nl/p4313_Osram-BASIC-T5-short-6W630-(21cm).html

No guarantee the lamps will have the same phosphor composition, but the color code matches.