XRF analysis of a WG Daytona

[doubles08]

I couple of people have asked what individual metals make up the actual alloys of various Rolexes, specifically the WG versions.

I was in a coin shop the other day and we were talking about testing the purities of various gold coins when it occurred to me that I could have my WG Daytona tested too. (XRF scanning is a non-invasive procedure, so the coin (or watch) is not damaged.)

The results of the spot we tested are below:
Gold 78.5%
Palladium 14.0%
Copper 7.8%
Silver - trace amounts

I'm not sure why the gold portion is not exactly or near 75% (as it should be), but maybe it has something to do with the unevenness of the way the alloy is mixed. Maybe a metallurgist or chemist can weigh in?

But I always wondered what made up the 1 part in 4 on a white gold Rolex that was not gold, and there you have it: Palladium and copper.

[Chiboy]

Hmmm, seeing how Rolex manages things in the manufacturing arena, I would have expected gold to make up 75.000000001% of the metal.

[AK797]

Cheers for that, thought there would be less copper in the WG.

[Racerdj]

Very interesting!

[RichM]

Great info. Thanks.

[vladamir15]

Nice info

[ap1]

Well done - happy to see the gold overweight versus the others

[bradyb]

Interesting that there's so much copper and surprising there's no platinum. I had previously assumed that the remaining 25% was mostly palladium and platinum, with small amounts of copper and silver.

I have a palladium wedding band and it's surprising how soft it is.

[TheRolexKingofLV]

Great info

[AP8ESQ]

I thought Rolex used actual platinum in the WG mix? Interesting...

[Busyboy]

Originally Posted by AP8ESQ

I thought Rolex used actual platinum in the WG mix? Interesting...

Same here

[GreenLantern]

Good info. Sounds about right to me, though. No reason to use Platinum instead of Palladium, to be honest. It also adds a bit more weight than Palladium would, and that might be unfavorable in their mind (considering gold's already high weight). Also helps their Platinum watches have significantly more heft than their Gold watches, which adds to their appeal.

[dadonn2]

Gold 78.5%
Palladium 14.0%
Copper 7.8%
Silver - trace amounts

This adds up to 100.3% plus the trace amount of silver. Sounds like something is amiss.

[doubles08]

Originally Posted by dadonn2

Gold 78.5%
Palladium 14.0%
Copper 7.8%
Silver - trace amounts

This adds up to 100.3% plus the trace amount of silver. Sounds like something is amiss.

0.3% is within tolerance.

[Abdullah71601]

Originally Posted by dadonn2

Gold 78.5%
Palladium 14.0%
Copper 7.8%
Silver - trace amounts

This adds up to 100.3% plus the trace amount of silver. Sounds like something is amiss.

Originally Posted by doubles08

0.3% is within tolerance.

Agree. This amount of variation is normal for XRF.

Let's not get into significant figures.

[dadonn2]

Originally Posted by doubles08

0.3% is within tolerance.

Did not know that.

[rootbeer7]

In 20 years time as well as worrying about dials, hands, bezel, and over-polished cases, we can obsess over the gold content!!

[osamu]

Cool I've used an XRF, but never thought to use it on my watch. Given I don't have a gold watch maybe doesn't matter too much, but I supposed I could use it on 904L and see what comes up.

[meganfox17]

Omega's proprietary patented 18K rose gold alloy a.k.a Sedna gold 1st seen in the Omega Constellation Co Ax Cal 8501 in 2013 has the same composition in varying alloy ratios minus the traces of Silver

My Guesstimate

Gold : 75 - 78.5 %
Min 75 % but I believe the actual % is less than Rolex 's WG

Copper : 20 - 22. 9 %
Copper content must be less than 23%


Palladium : 1.1 - 2.0 %
Palladium content must be >1%
In the bigger picture , 18 kt Gold per gram is more valuable than t###r p☆♤¥$ but white truffles are worth twice as much

Sent from my SM-G900F using Tapatalk

[douglasf13]

Originally Posted by meganfox17

In the bigger picture , 18 kt Gold per gram is more valuable than t###r p☆♤¥$ but white truffles are worth twice as much

Judging by those prices, I'm guessing this must consist of both 18K gold and tiger penis!

[WatchinMD]

Very interesting

[Xerxes77]

Interesting

[1William]

Interesting, thanks for the information.

[watchwatcher]

Thanks for that.

[locutus49]

I trust ROLEX OVER A MACHINE THAT MIGHT NEED ADJUSTMENT.

[DeeTee]

Does the age of the watch have anything to do with it?
Doesn't WG and RG oxidize?

[Danex]

Perhaps 18k gold is 75% gold by volume and the machine measures by weight?

[991]

Very cool info.

[Emreozcan]

Metallurgist here: When it comes to alloying metals there are tolerances with min-max values. When we add the different determination methods (XRF analysis in this case) and different calibrations of the devices (for instance 2 different XRF devices can even find different results from same sample) we see these varying results. In practice most precise measurement devices can be found either in Universities or factories where they regularly cast metal alloys.

Bright side is that you have 3.5 Weight % more gold :)

Cheers.

[doubles08]

Originally Posted by Emreozcan

Metallurgist here: When it comes to alloying metals there are tolerances with min-max values. When we add the different determination methods (XRF analysis in this case) and different calibrations of the devices (for instance 2 different XRF devices can even find different results from same sample) we see these varying results. In practice most precise measurement devices can be found either in Universities or factories where they regularly cast metal alloys.

Bright side is that you have 3.5 Weight % more gold :)

Cheers.

Thanks. An expert interpretation of the results is appreciated.