"New spines emerge as a glistening white or golden yellow." That simply means artificial color has been added to the plants and what you see is entirely unnatural. If they survive the dye to grow, they will never, ever have this appearance again. At least they are telling you that, but I wonder how many people realize that as soon as the color is gone, it is gone forever and ever and ever. Also, I wonder what the plant looks like as the artificial color is fading and how long it takes for it to completely disappear. In the first case I'd think it probably gets unattractive. In the second, since cacti in general tend to grow slowly, that fading color might make it look ratty for a long time.
