PD999 is just a content code. But it doesn't mean which gold is which silver.

For example, silver can also be expressed as PD999. The passive silver content reached 1G, and the silver content was 0.999.

And if the landlord bought platinum at that time, it means that your platinum is the best platinum at present, because the content is quite high. Sometimes you can see values such as PD950 PD930.

It shows that the metal content is only 0.950 and 0.930, which is not as good as PD999 with high content.