Japanese platinum case in the 50's-60's

Dear IWC forumers,

Recently I acquired Platinum Cased Cal.8531. That has incorrect case No. and hallmark "Pm 900" In Japan, We sometimes find such watches (Cal.89, Cal.85XX etc...) and have considered as "Marriage" But exactly not. It's a sort of Cress-Arrow case.

I would explain Japanese Platinum Case though my poor English. In the 50's, ISOMURA Co. (importer of IWC watches till 1964) made Platinum Case for IWC watches under permission of IWC Schaffhausen. The reason is to avoid murderous taxes (30% import duties, 13% precious metal tax). Rolex, Gruen and some watchmakers followed the lead in Japan. Japanese case was inscribed "Pm900" and 140263 (Probably, some has 5XXXX). Hallmark "Pm900" was only seen in Japanese Platinum Product until quite recently. I've heard from retailer at the time that almost 85% of Platinum IWC sold in Japan has ISOMURA Case. But the rest of 15% has Original Platinum case! (Once seen)

For your reference, original platinum was over 1,000,000 yen in the 50's and 60's while ISOMURA case was 200,000 yen. And I would add that Da Vinch SL Platinum listed 8,000,000 yen in 1972! But who dare to buy?

Purist might dislike these marriage, but It is interesting that Japanese realized that IWC is worth wearing not Gold, but Platinum.

Thanks to Mr. Fujiwara and Sugiyama of Probus Scafusia, IWC club Japan.

Regards,
Nikator from Japan

sort of Cress Arrow?

Hi Nikator,

Very interesting indeed! Do you have photos? Is there the moon-and-crescent stamp for Cress Arrow anywhere --or markings other than "Pm900" and 140263?

Regards and thanks,
Michael

Back side of 8531Pt

Hello MF,

NO special crest like Cress Arrow inscribed. Simply There are "140263" and PM900 (or PLATINUM) in Back case.

Only Japanese government has accepted such simplified hallmarks on platinum products!
Thus I say If you find "PLATINUM"or "Pm900" cased IWC, that was ISOMURA case, made in Japan.

Regards,
Nikator from Japan

P.S I really enjoyed your interview with Mr.RH...Thanks

Very interesting...

Tha case is fully IWC signed, but for the serial number on digit is missing. Probably the person staming the case, just forgot one digit (at the end)?

Is it possible that the cases were sent from Japan to switerland to encase the movements?

Do all known IWC Platium watches have a just 6 digit number?

Somone should check in the archives, if the watches 1'402'63x are in the lists as platiunum watches....

Thanks for sharing this information with us.

Best regards

Ralph Ehrismann

Additional Infomation...

Dear Ralph,

We met 9 platinum vintage IWCs in Japanese Market.

1. Cal.89
2. Cal.853 or 8531
3. Cal.8541(B, maybe)
4. Ladies modes in 60's

One has original case no (160XXXX)and helvetia hallmarks (PT
950), but four models has No.140263 case! At least, We can say
that Original PT case was also made in 50's or 60's.

Original platinum case was not only for Cal.87 and Beta21 quartz!

Reagrds,
Nikator from Japan