As funny as it sounds, though synthetic gemstones are much more affordable than their natural counterparts, they are actually the gems that possess the more flawless appearance. Synthetic gemstones...
Yes, stone is a natural substance, not man-made.
Topaz is a mineral. Amber is fossilized tree resin.
Depends on the type. Metals such as tin, aluminum and titanium are natural. Alloys such as steel and bronze are synthetic.
natural, starches are a form of sugar, potatos have a form of starch. I'm sure there are also some synthetic ones as well.