If you love the gemstone, then it can't have been an error of judgement. You can always reset the stone in the future 
For me, its Gemporia changing from selling gems that are new and unusual to viewers (well, to me anyway), that were good value for money and that people enjoyed wearing, to flogging overpriced and overtreated stones in foil or wire weight settings as "legacy" and "heirloom" pieces.
There's no fun in the channel any more either: it's all hard sell and buy now, or else! So if you're still loving your sphene four years on, it can't have been a bad purchase