Airoldi set - necklace and earrings

I bought this set on Kingsday 2015. The seller sold old stock from his parents jewelry shop for € 1,00 a piece. The old price tag shows a price in Dutch guilder which means is was priced before 1-1-2002.

So it's in my closet for almost 2 years. Last week I saw it and took the time to google about this mark. I never heard of Airoldi before. It's an Italian jewelry designer who designed a lot in gold plated silver.
Right away I checked this set and indeed there are silver marks (800)