First time soldering 9ct white gold

Hi everyone, another newbie-ish question about white gold. I purchased 1.5mm white gold wire from cookson for some stack rings. As it was my first attempt I bought some smaller solder amounts off ebay (cooksons starting price is around £50 and I didn't need that much). However soldering the ring, it seems the solder temperature of whatever I bought was much higher and the ring ends basically started to melt onto themselves whilst the solder remained unchanged.

Without it obviously being fraudulent metal (seemed a genuine goldsmith seller, chasing this up with them now) I just wondered if anyone had any ideas or could help me out regarding working with 9ct white gold and what went wrong?

Kind regards x

9ct white gold is very similar to sterling for soldering. The only difference I have found is that it can melt and collapse during the process.
You will note that Cookson provide only medium solder to counteract this, with a melting point of around 730°C.
It is also wise to work in a darkened area to assess the glow, and make sure the whole piece reaches soldering temperature, before homing in on the joint

To test the solder you have bought, melt a scrap on some waste metal, side by side with some easy silver solder and some flux. They should melt at roughly the same time. If the stuff you have bought lags behind, it is not safe to use for this purpose. Dennis.