The key question - for what?
PVD technology is widespread. So, there is no reason for a manufacturer to cheat with gold plating. Without real gold plating jewelry will have worse quality, but it won't be cheaper.
The best way to check jewelry is to wear it - the higher jewelry durability, the better gold-plating is used.

In a laboratory setting we tested our jewelry for 2 weeks in salted water. In real life girls from our team wear our jewelry for more than a year, swim & sunbathe.

In normal conditions plating can stay without discoloration or tarnishing up to 24 months, and more.

So we made sure that by Moppie jewelry is tarnish-free and water-resistant.

No. Actually gold-plating lasts much longer, year and more. Glozzo Jewelry can be used daily: in the sun, in the sea and shower.
To increase durability, avoid frictions and physical impact on jewelry. Direct physical damage can destroy the plating.
Using your jewelry with care will allow it to last longer.