Rare earth's metals
All of the base metals on Earth such as iron, gold, silver, platinum, zinc, copper, etc. are not originally made on the earth, because the earth is a planet, and planets do not have enough energy to create these elements from atoms. The base metals can be made only in very powerful nuclear reactors, in stars.
QUOTE: "Our work shows that
most of the precious metals on which our economies and many key industrial
processes are based have been added to our planet by lucky coincidence when the
Earth was hit by about 20 billion billion tones of asteroidal material."
QUOTE: "The heavier the
star, the more different elements it will make, and the shorter its life. Our
Sun, on the other hand, will not make much past helium. In addition, it is only
the more massive stars that go supernova. So, if a star makes iron, it will
likely go supernova."
What we see in the two quotes above is that metallic elements have been delivered to Earth, as well as to the other inner planets in our solar system, from a star that is not the same as our sun.
The size of stars mentioned in the second quote above isn't an issue here. We will see later, in the section about stars and the nature of the second sun that there are stars, classified as white dwarfs, have been observed to produce rocks and metals, and without exploding as supernova.
Metallic elements like iron can be either pure metals or metals as ingredients of rocks. These rocks are the same rocks that make up ocean floor and mountains. And since there is no rocky mountain on Earth older than 200 million years, and there is no ocean floor older than 200 million years, we have to say, based on the common sense, that the metals along with their containing rocks, have arrived to Earth around that time only, about 200 million years ago.
QUOTE: "there are few
250 million-year-old rocks left on Earth. Most have been recycled by our
planet's tectonic activity"
The link above is about the Permian-Triassic extinction event; the quote says that there are only "few" rocks older than 250 million years left on Earth. The absence of rocks is attributed to a "theory" that hasn't been proven to exist before 200 million years! The surprise is that the so-called tectonic activity that has "recycled" all of the rocky mountains on Earth, has left huge sandstone mountains untouched! And these sandstone mountains do not contain metals at all.
The supposed few rocks that are older than 250 million years in the quote
above are very likely meteorites landed on Earth from outer space, just like the
land on Earth nowadays from time to time. And these meteorites
can be rocks, metals, or rocks containing metals.
The Earth Inner Core
The earth inner core, that is made of iron and nickel, isn't as old as the earth itself, as some might think, but it is an added part at a very late time, and it is getting bigger. Some scientists give it an age of about 500 million years only, compared to the Earth estimated age, 4 billion years.
QUOTE: "The inner core is a relatively recent addition to our planet
and establishing when it was formed is a topic of vigorous scientific debate
with estimates ranging from 0.5 billion to 2 billion years ago."
It is said that the Earth's tectonic activity recycles the sea floor and rocky mountains every 200 million years, but does it also recycle the Earth inner core?!
Other than rocks that fall down from space as meteorites, there is no evidence to show the existence of metals on Earth since the beginning of the Earth history; not even inside the earth internal layers.
The most likely scenario that has led to the creation of the earth core is this: when the second sun started firing gamma rays at earth, and because it was a very near star, the rays were extremely powerful, so they caused ionization of gases inside the earth's mantle that led the mantle to explode. Debris from the second sun, mainly rocks, fell down inside the mantle and formed the sea floor. The rocks that stayed inside the mantle got melted and released their metallic elements, including iron. The extracted iron started to sink to the earth center and concentrate there to form the inner core. So the formation of the earth core is an ongoing process until this day; that is why the core is getting bigger. Since there was no iron or any other metal on Earth before 200 million years, it is impossible for the earth core to be older than 200 million years.