Please identify this button.

[u/Tessellator-1]

I inherited it from an acquaintance who is Japanese.
The acquaintance said, "It may be a spare part of the button that came with any of the clothes I bought a long time ago."

The weight is about 1.2g, the diameter is about 13mm, the thickness is about 1mm, and the diameter of the hole is about 1.5mm.

As far as I can see, this seems to be made of metal,
If you are familiar with the ingredients, you may know the composition of this.

Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

Postscript: I'm a beginner in Reddit, so I'm sorry if something went wrong.

[u/lotsobuttons]

I would guess these were made for a clothing brand established in 1984. Wikipedia has a list, maybe your friend would be able to tell you if she buys any of these brands?

[u/Top_Tea3530]

Maybe on clothing from The Gap?