Spend Huge Amount of Money for Damaged Jewelry

I bought a Pendant and Chain on 21 Dec at Port Alfred Branch (Ashwin Wotbooi) 9ct Pendant *** - R1699.00) for my wife for Christmas. It is a Heart Pendant with an Infinity Sign through it Gold and Chain. The Heart is Diamands or Cubics. So the first time she wears this chain, it breaks. When we go back to Jhb she took it to Alberton City Branch on 12 Jan and they said they will send it in for repairs. On Monday the 18th of Jan my Wife phoned them to ask if it is back and they said yes, it is ready she can come fetch it. She gets there the afternoon and they open it and tell her no they cannot repair it (wear and tear), she must wait another 3 days so they can source a new from another store. So they never open this and wasted her time and money to go out. She insisted that they take one off a pendant there in the store as she is not coming back again, which they did with long faces and attitudes as their Manager never taught them to open the Repairs when they come back?? They put it in a box and she left. Then when she got home, one Diamond or Cubic was laying in the box and came out. WHAT QUALITY DO YOU SELL TO CUSTOMERS FOR R1700?? EITHER YOU REFUND ME OR SORT THIS OUT!!!