Osmium, rhodium and iridium are probably the rarest metals found in the Earth's crust with average concentrations of 0.0001, 0.0002 and 0.0003 parts per million by weight respectively.
Astatine: The chemical element astatine has the atomic number 85 and the symbol At . It belongs to group 17 and period 6 of the periodic table. It is the rarest naturally occurring element in the crust of the Earth and only appears as a decay product of several other heavier elements.
Almost every galaxy can be classified as a spiral, elliptical, or irregular galaxy. Only 1-in-10,000 galaxies fall into the rarest category of all: ring galaxies.
Ununennium, or element 119, is a predicted chemical element. Its symbol is Uue. Ununennium and Uue are substitute names made by the IUPAC, (meaning "one-one-nine-ium" in Latin) until permanent names are made. Ununennium is the element with the smallest atomic number that has not been created yet.
Uranium was discovered in 1789 by German chemist Martin Heinrich Klaproth. It is the heaviest naturally occurring element in the universe and is naturally radioactive. Its nucleus is unstable, so the element is in a constant state of decay, seeking a more stable arrangement.
Astatine is the rarest element on Earth; only approximately 25 grams occur naturally on the planet at any given time. Its existence was predicted in the 1800s, but was finally discovered about 70 years later.
Scientific element: Francium
The most expensive and second rarest natural element.
The rarest stable metal is tantalum. The rarest metal on earth is actually francium, but because this unstable element has a half life of a mere 22 minutes, it has no practical use.
Platinum Group Metals. Osmium, iridium, palladium, ruthenium and rhodium are typically grouped with platinum and known as platinum-group metals or elements (PGMs or PGEs). These elements are rare on earth, but abundant in the rest of the universe.
Astatine is the rarest naturally occurring element. The total amount of astatine in the Earth's crust (quoted mass 2.36 × 1025 grams) is estimated by some to be less than one gram at any given time.
Einsteinium is an element with a famous name that almost no one has heard of. With 99 protons and 99 electrons, it sits in obscurity near the bottom of the periodic table of chemical elements, between californium and fermium.
Iridium is one of the rarest elements on Earth. It is found uncombined in nature in sediments that were deposited by rivers. It is commercially recovered as a by-product of nickel refining. A very thin layer of iridium exists in the Earth's crust.
Astatine is therefore the rarest element in the periodic table because it's the hardest to produce. So hard to produce, in fact, that the scientists who first created it in 1939 couldn't detect its existence directly and had to resort to a trick.
Plutonium. Pretty much all of the radioactive elements are cool. Plutonium is particularly awesome because it truly does glow in the dark.
Aluminum is a chemical element with symbol Al and atomic number 13. Classified as a post-transition metal, Aluminum is a solid at room temperature.
Meet nihonium (Nh), moscovium (Mc), tennessine (Ts), and oganesson (Og) -- elements 113, 115, 117, and 118. The four new elements have just been given names.
Indium - Element information, properties and uses | Periodic Table.
Unbinilium, also known as eka-radium or simply element 120, is the hypothetical chemical element in the periodic table with symbol Ubn and atomic number 120.
A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".