Lost: amethyst necklace on gold chain - stolen from Navaria Beach Apartments Abades

I am hoping anyone can help on here.

My mums necklace  was stolen from Navaria Beach apartments in Abades by the house keeping/reception staff in October last year, I have offered a reward with no question asked of 500 euros for its safe return. It is a gold necklance 18 inch chain with amethyst purple, with crushed diamonds on the outer. My mum gave it to me before she died and I am heart broken I have lost it.

I search the second hand jewelry shop posts and buy sell swop tenerife nearly every day to see if i can see it. 

please contact me 0044 7970388116 if you have it or see it please - I have friends in el salto who will come and pick it up with the reward no questions asked.