Either.
However the natural form is rare on the surface of the earth, but higher levels are in some igneous rocks, some lavas, and all meteorites.
Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named the iridium for the goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts.
Metal that is a naturally occurring element.
natural
Acrylic is a synthetic fiber made from polymers derived from petroleum or natural gas. It is not a natural fiber like cotton or wool.
It is a synthetic addition polymer.
It is synthetic, but what we use to make concrete is natural AND synthetic.
is bromine natural or synthetic?
Polyester is synthetic.
it is synthetic
they are synthetic.
Yttrium is a natural element found in the Earth's crust. It is not a synthetic element.
Iridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named the iridium for the goddess Iris, personification of the rainbow, because of the striking and diverse colors of its salts.
Metal that is a naturally occurring element.
its natural
natural
natural
Iridium is a transition metal very dense, practically unreactive, resistant to corrosion, has many oxidation states and natural isotopes, etc.