That’s not “backing”: nobody buys specifically to keep gold prices up or to legitimise the trade, they just use it as a commodity to make their creditworthiness believable and storing their value in a practical way. They are leveraging a pre-existing market, not backing it.

(As a side note, this role for gold is clearly legacy: look at how little gold China stores, compared to their overall reserves.)

> their creditworthiness believable

this not backing ?

> look at how little gold China stores

by metric tones china is on 6th place in world, what do you mean ?

>>[Governments use gold to make] their creditworthiness believable

> this not backing ?

It's the opposite. Originally you said "Gold Market is backed by Governments". This is governments being (partially) backed by gold.

>> look at how little gold China stores

> by metric tones china is on 6th place in world, what do you mean ?

Their economy is the largest in the world. How much smaller are their gold holdings, compared to those in first place?