Vintage Necklace with Pendant semi-precious stones

Necklace Sandstone choker style brown-reddish color with pendant in the center made of semi-precious stones in turquoise blue, dark blue, red and green. I don’t really know the names of the stones only the turquoise one. Just was told they are semi-precious stones. The choker necklace is round sandstone beads and has opening brooch made of gold plated material in both ends to interchange pendants if you have or buy more. It was purchased in Barcelona, Spain in the ‘90s. For more questions contact me. Only serious buyers. Priced to sell.