its really interesting stone, it has cut issues but the colour is really nice, no brown undertones but a touch of grey at times (it shows in the evenings, or in overcast sky) and it changes from lilac, to medium purple, pink, blue tones....really cool stone! I think the "collar" you mention is above the white gold shank and surrounds the pavilion? its rose gold as well as the prongs but its hard to see on the pictures! the only white gold is the band itselfyou did BETTER than any of the settings that we were talking about! I love the pure simplicity of this setting. it shows off your stone wonderfully. for some reason, I'm drawn to the "collar" of WG around the bottom (pavilion) of the stone. it's fascinating! I also love the large/thick prongs that highlight the RG.
I can imagine that you've worn it constantly...I would too! I can't believe the stone changes color based on the light. it sounds amazing!

have you decided to set your pink spinel yet? I love the colour of it, its so delicate!