I thank you so much for bringing up one of my favourite subjects i.e. the very vast collection of jewels worn by HM Queen Sofia. Let me start off with her diamond necklaces:
Worn by the then Princess Sofia of Greece at ther wedding in 1962. Also worn by Queen Letizia.
Diamond Tassle Demi-Parure
Square Diamond Reviere
Diamond V Shape Necklace: Often a Grey pearl is worn as pendant.