Opinions requested on lume from circa 1960 for 1675

[georgetownhoya]

Hi sensui - congratulations on a beautiful watch! That watch actually was found by me. I bought it from the friend of the original owner who inherited it in the mid-1990s after his friend passed. I was offered the watch by e-mail after the gentleman saw the Reference Points video and article on HODINKEE and spoke with the elderly gentleman who owned it for hours about the watch, which was essentially unworn and untouched since he received it.

As others have mentioned, there is a run of GMT-Master reference 1675 examples with that greenish, long-glowing and low-to-no radioactivity luminous material, typically with an inside case back production of "IV.60" (meaning the case was made in the fourth quarter of 1960, with the watches being assembled and tested well after that). I believe that this lume mixture on this run of GMT-Masters, as well as the "Tulip" or "Tulipino" Submariner reference 5512s was strontium aluminate. Here is how Wikipedia describes it: "Strontium aluminate is an aluminate compound with the chemical formula SrAl₂O₄. It is a pale yellow, monoclinic crystalline powder that is odorless and non-flammable. When activated with a suitable dopant, it acts as a photoluminescent phosphor with long persistence of phosphorescence."

Alex Ciani recently wrote this on Instagram: "It’s common knowledge that tritium replaced radium as the luminous paste on watch dials in 1963. It wasn’t however the first less-radioactive material to be used for this purpose: starting around 1960 Rolex had already been using - alternatively to radium - strontium aluminate, a mineral based compound still used today for many applications. Those dials are easily recognized by the vibrant, greenish color and intense luminescence, something that has often misled the judgement of many vintage watch experts back in the day, with the consequence that a number of perfect factory dials ended up being “relumed” with very questionable results."

If you have any questions, please feel free to reach out to me. Eric Wind of Wind Vintage

[HarryLime]

Originally Posted by FrenchBigCrown

Why?

Watch the OP's video - it's more or less the same as that.

Because the majority of the people posting here has never seen 60 year old lume glow for this length of time. If yours is untouched and does the same, it basically settles any debate.

[roh123]

Originally Posted by HarryLime

Because the majority of the people posting here has never seen 60 year old lume glow for this length of time. If yours is untouched and does the same, it basically settles any debate.

His dial is approx 2 years later as it has an underline. It also has very different lume and the watch carries a number of service parts. I think it is wiser to read Erics post above where he shares his knowledge on the topic at hand.

[swish77]

Originally Posted by georgetownhoya

Hi sensui - congratulations on a beautiful watch! That watch actually was found by me. I bought it from the friend of the original owner who inherited it in the mid-1990s after his friend passed. I was offered the watch by e-mail after the gentleman saw the Reference Points video and article on HODINKEE and spoke with the elderly gentleman who owned it for hours about the watch, which was essentially unworn and untouched since he received it.

As others have mentioned, there is a run of GMT-Master reference 1675 examples with that greenish, long-glowing and low-to-no radioactivity luminous material, typically with an inside case back production of "IV.60" (meaning the case was made in the fourth quarter of 1960, with the watches being assembled and tested well after that). I believe that this lume mixture on this run of GMT-Masters, as well as the "Tulip" or "Tulipino" Submariner reference 5512s was strontium aluminate. Here is how Wikipedia describes it: "Strontium aluminate is an aluminate compound with the chemical formula SrAl₂O₄. It is a pale yellow, monoclinic crystalline powder that is odorless and non-flammable. When activated with a suitable dopant, it acts as a photoluminescent phosphor with long persistence of phosphorescence."

Alex Ciani recently wrote this on Instagram: "It’s common knowledge that tritium replaced radium as the luminous paste on watch dials in 1963. It wasn’t however the first less-radioactive material to be used for this purpose: starting around 1960 Rolex had already been using - alternatively to radium - strontium aluminate, a mineral based compound still used today for many applications. Those dials are easily recognized by the vibrant, greenish color and intense luminescence, something that has often misled the judgement of many vintage watch experts back in the day, with the consequence that a number of perfect factory dials ended up being “relumed” with very questionable results."

If you have any questions, please feel free to reach out to me. Eric Wind of Wind Vintage

Fascinating. Thanks for sharing the info.

[roh123]

It’s interesting as Strontium aluminate is what’s much later was used for Superluminova. I didn’t know this may have been used by Rolex this early but it would explain the strong and long glow on these watches. Other lume material that was speculated to have been used in this era is Promethium 147. More specifically before the underlines in 1963. I really miss reading the long discussions on VRF where John (fatboyharris) shared his wide knowledge regarding this. Bit of a shame we don’t have those discussions anymore.

Thanks for pitching in Eric and confirming.

[suligeo]

From 1967


https://www.instagram.com/vintage_georgex/

[greekbum]

Interesting a large arrow that glows like that

Originally Posted by suligeo

From 1967


https://www.instagram.com/vintage_georgex/

[springer]

Originally Posted by suligeo

From 1967


https://www.instagram.com/vintage_georgex/

The bluish green color is indicative of a relume job for me. Especially that glowing green lume on the large 24-hour hand.

[suligeo]

No Springer it’s green. The UV light makes it blueish. This green is zincsulfade with tritium.
For this period correct





https://www.instagram.com/vintage_georgex/

[springer]

[QUOTE=suligeo;10726367]No Springer it’s green. The UV light makes it blueish. This green is zincsulfade with tritium.
For this period correct


If you think it is correct, then my opinion remains mine. I've never seen a large, green-glow 24-hour hand. If you like it, and think it is correct, then that's all that is important. My opinion differs.

I've been buying and collecting GMTs (200 plus watches) for over two decades and have never seen that hand before with green glowing lume. Additionally, the hands look "brand new" which makes them highly suspect for me.

Notice the 24-hour hand does not glow green on this circa 1966-67 GMT 1675.

[suligeo]

From what I know, and more collectors with knowledge, the first big GMT hand 1675 between 1966-1968- probably Serial late 1.6Mio until low 1.8Mio with MK1 longE came with a mixture Tritium/zincsulfade which glows still today. Strong green but short time.
That’s not new and I wonder that you and Nick never heard about it?!

The 1675 you show looks same. Why gmt hand glows different? You believe this handset was born together?
Who knows?! In 50years many can happen and not all things ageing same.


https://www.instagram.com/vintage_georgex/

[sensui]

Originally Posted by georgetownhoya

Hi sensui - congratulations on a beautiful watch! That watch actually was found by me. I bought it from the friend of the original owner who inherited it in the mid-1990s after his friend passed. I was offered the watch by e-mail after the gentleman saw the Reference Points video and article on HODINKEE and spoke with the elderly gentleman who owned it for hours about the watch, which was essentially unworn and untouched since he received it.

As others have mentioned, there is a run of GMT-Master reference 1675 examples with that greenish, long-glowing and low-to-no radioactivity luminous material, typically with an inside case back production of "IV.60" (meaning the case was made in the fourth quarter of 1960, with the watches being assembled and tested well after that). I believe that this lume mixture on this run of GMT-Masters, as well as the "Tulip" or "Tulipino" Submariner reference 5512s was strontium aluminate. Here is how Wikipedia describes it: "Strontium aluminate is an aluminate compound with the chemical formula SrAl₂O₄. It is a pale yellow, monoclinic crystalline powder that is odorless and non-flammable. When activated with a suitable dopant, it acts as a photoluminescent phosphor with long persistence of phosphorescence."

Alex Ciani recently wrote this on Instagram: "It’s common knowledge that tritium replaced radium as the luminous paste on watch dials in 1963. It wasn’t however the first less-radioactive material to be used for this purpose: starting around 1960 Rolex had already been using - alternatively to radium - strontium aluminate, a mineral based compound still used today for many applications. Those dials are easily recognized by the vibrant, greenish color and intense luminescence, something that has often misled the judgement of many vintage watch experts back in the day, with the consequence that a number of perfect factory dials ended up being “relumed” with very questionable results."

If you have any questions, please feel free to reach out to me. Eric Wind of Wind Vintage

Hi there Eric. Very glad to see you chime in and add some knowledge/experience to a fascinating/interesting discussion.. after all that is the goal of all this... Education and see where people lie in their opinions as a lot of this hobby isn't resolute... As they say.... Clear as mud. But thanks also for sharing the history of the watch and expanding on this series of lume from this transitional era.

To everyone that's commented and shared their experience/knowledge I thank you as well. I think the topic is certainly interesting and we're all learning one way or another. As previously mentioned by springer already, everyone is entitled to an opinion and I see no problems discussing it as long as everyone has valid points to reference for everyone.

[springer]

Originally Posted by suligeo

From what I know, and more collectors with knowledge, the first big GMT hand 1675 between 1966-1968- probably Serial late 1.6Mio until low 1.8Mio with MK1 longE came with a mixture Tritium/zincsulfade which glows still today. Strong green but short time.
That’s not new and I wonder that you and Nick never heard about it?!

The 1675 you show looks same. Why gmt hand glows different? You believe this handset was born together?
Who knows?! In 50years many can happen and not all things ageing same.


https://www.instagram.com/vintage_georgex/

The reason Nick, me and others that I talked to today never heard of it before is because in our opinion it didn't happen. Sorry, that's an opinion not only shared by me but others that have been collecting and in the business for decades unlike the newbies with all these newfound claims.

But, if it works for you, then that's wonderful. I have no reason to discuss it further.

[springer]

Originally Posted by springer

The reason Nick, me and others that I talked to today never heard of it before is because in our opinion it didn't happen. Sorry, that's an opinion not only shared by me but others that have been collecting and in the business for decades unlike the newbies with all these newfound claims.

But, if it works for you, then that's wonderful. I have no reason to discuss it further.

S, disregard my comments regarding the early, large 24-hour hands not having a green glow under UV light. I am a little mistaken it seems. I've had a couple examples sent to me that are in the 1.7 million serial range that glow green under UV. Under the UV light in a darkened room, the lume glows green and once the UV light is shut off, the glow remains for 7 to 8 seconds before quickly dissipating.

[suligeo]

Yes Springer, the first batch( there are 3 different MK1 1675 dials)
MK1 longE has the mixture Tritium/zincsulfade which still glows today under UV. It glows not long but strong. You just have to google 5 minutes and you can read all night after strong coffee.

Only between 1966-1968. Actually I love more my vanilla 1675 instead of glowing( greenish dial) but it connects two worlds. A 50years old vintage piece that glows strong as the new ones.

Some more examples

https://robertmaron.com/product.php?productid=20654

https://www.watchpatrol.net/de/eintrag/833741/

https://www.watchpool24.com/de/30734...ox-und-papiere

https://watchcharts.com/listing/1418537

https://gmtmaster1675.com/mark-1/

https://www.r-l-x.de/forum/showthrea...urks-II)/page5


https://www.instagram.com/vintage_georgex/

[suligeo]

As I said, over half century old but sharp...



https://www.instagram.com/vintage_georgex/

[b.k.]

Here’s mine with 1.4m serial/

https://drive.google.com/file/d/17v-...w?usp=drivesdk


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