friend of mine, his parents own a well known jewelry store in tristate area. His mom only wears fake jewelry (and everyone assumes its real)
lol its like driving a high end car with a nissan engine, or those people who wear fake Ferragamo belts and shoes. The jokes not on the people who think your wearing the real thing, its on the person wearing it. At the end of the day if your eyeing that huge diamond and you can't afford it...chances are people may think your wearing a fake. As for your friends mother she could do what she wants lol she can honestly wear something for a month clean it and put a ticket on it and sell it to you and me and we wouldn't know.
(She also prob doesn't feel the specialness of a piece of jewelry, it happens when your so exposed to something)
again for me and you who don't own jewelry stores. get educated and when you buy your next piece you will be able to break it down. Cost of gold of item + how many ct (many stores don't put in high quality stones which if you know this fact can help you negotiate a better price) = value and then subtract the value from asking price and you have markup and design!
This is very much back of the envelope math but the more you learn the more you can tweak the equation.