Why does my porcelain crown look gray? (photos)

So about a week ago I got placed an all porcelain crown with a titanium abutment and implant. The color of the crown matches my other teeth in some light but in some it looks grey and really stands out. Would switching the abutment to zirconium help? My dentist mentioned it my break if we switch to zirconium due to it being a canine tooth. I want to know what are you guys' opinion on how to correct this problem and what is the cause? Thanks in advanced.