<prompt> Human: Got a really weird offer today. Buy for 10.000 CHF unprocessed certified diamonds and get guarantees 20 return of investment. If it was not from one I normally trust doing my insurances etc. I would default to consider it a scam. I thought diamonds was a scam in value but googling i keep finding pages saying diamond is a legit thing to invest in assuming you know what to look for. Anyone met this as a legit thing or should I just run away knowing nothing can realistically offer a 20 return of investment ?  <response>: If you could guarantee a 20 return in one year, they wouldnt need to send out investment solicitations, Warren Buffett would be dropping a billion dollars on them. 