Gay Freres bracelet confusion

 I have recently taken a liking to the "Skinny" Ingenieur SL and I have a question for the forum: I have found a couple of examples of the IWC Ingenieur in gold (references 9225 and 9230, I believe) that have a gold bracelet but a clasp that seems to be made of stainless steel, on which a hallmark has been applied. This seems to make no sense to me. Why would the hallmark be on a part of the bracelet (the deployant clasp) that seems to be made of stainless steel (why would Gay Freres do something like that?)

Here are some examples:
www.chrono24.sg/iwc/ingenieur-18ct-gold-chronometer-herren-neuwertig--id2776514.htm

www.chrono24.sg/iwc/ingenieur-sl-lady-ref-6704-in-18k-gelbgold--boxpapiere--aaw--id4579761.htm

www.chrono24.sg/iwc/ingenieur-sl-jumbo-quartz-18kt-massivgold--id2769968.htm

Here they claim that the clasp is made of white gold (why? It makes little sense to me):
www.watchcentre.com/product/iwc-18k-y-g-champagne-omani-crest-dial-ingenieur-sl-gents-9230/5637

What do the other IWC aficionados think?

Thank you in advance for your time and for your immensely helpful forum.

Michael

Your conclusion is wrong.

All those deployant clasps were originally made of white gold.

But fraud exchanges to steel could be possible ?!

Thank you for your input, HEBE. You seem to be an experienced fellow. However, I have come across a number of IWC Ingenieur bracelets that are made of yellow gold, as I believed they should:

www.ebay.com/itm/IWC-INGENIEUR-SL-AUTOMATIK-9236-750-000-Vollgold-m-Box-Revision-26-1-16-auf-USB-/391727707196?hash=item5b34ca743c:g:Nb4AAOSwWxNYxv1t

www.ebay.de/itm/IWC-INGENIEUR-JUMBO-Herren-Automatik-Vollgold-750-Box-/151886445012?hash=item235d2339d4:g:sM8AAOSwTM5YymEk

I am pretty sure I have seen other Ingenieurs with non-white/steel/white gold clasps but I can't find them right now.

What is behind the discrepancy?

I have another question: why would the deployant clasps be made of white gold?

Now that I have become an IWC fanatic, I am determined to learn all I can about this. :)

It really is hard to determine the bracelet materials by these photos alone, but with some bracelets, the clasp sections may be too thin for gold to be used?

Well, I am not the designer of those clasps :-)

But, a golden watch with parts of steel would be very uncommon ?!

The alloys of yellow/red gold and white gold are different.

So, the robustness of white gold is better and some steel pins have the same color.

Maybe the reason for using it for later models and shifting from gold to white gold ?!

But just my own opinion.