help with pearl earrings

hi all acquired these from a bag of mainly rubbish but needed some clarification on what type. they seem original and the support has dan on it. googled and there was some relates to China anyone have any extra thoughts please chris

 

You've probably found as much as there is to find on the mark.
China produces a lot of costume and mainstream fine jewellery, it is impossible to know all the brands. I never put much effort in researching them, it doesn't add to the value.
You didn't mention if they are silver and real (cultured) pearls. Are they?

 

I believe yes to both thanks any

 

Think you are reading the letters upside down: try NVC - quite a bit of NVC jewelry on eBay.

 

Of course! I was wondering about the funny looking D.