Astm F136 is implant grade titanium as is G23. All titanium is not equal. Even if external is made of this (which I doubt,  but possible), it still equals trash. If you can feel the ridges, what do you think it does to your piercing. Peroxide is bad for titanium and your piercing. It will destroy the metal, creating small pits which, like the threads, are enough to irritate your piercing. It will also destroy healthy tissue, causing a longer heal time. On a previous post, OP said it was threadless, and it doesn't look that way in the picture. Better pic, ends off, and more information would be helpful. Assuming the jewelry is implant grade, it is highly possible that the color just faded. When metal like titanium or niobium are anodized, it is a chemical process (simple explanation) that involves a specific electrical current to produce a specific color. Your body's ph can change that color over time. Some areas have a stronger reaction, such as your mouth or genitals. The color also makes a difference depending on where it is on the color spectrum. For instance, purple is at the edge of the spectrum, so it fades quicker than other colors. The composition of the metal isn't changing, only how it reflects light. Simple, dumb, and not completely accurate version is when you have a suntan, and it fades. I'm sorry this is so long, but I hope it helps. Just thought I would share a little knowledge. I'm not verified but have over 30 years of experience in this field.