White Gold ? in nugget or flakes of Platinum iridosamine?

This was found again up in Hokkaido Japan while prospecting in an area said to have been Rich in Gold & Platinum back in the gold rush days, the rock is clearly quartz with small silver metallic flakes in it. Appears very much like rocks in the museum in Hokkaido that have white gold in them.
Re the comment I wonder why the Hokkaido rock museum would say white gold on their specimens? .

Must a variety of schools of thought re this .........any one with Knowledge please comment.

Thanks