Abundance of Elements
"Universe start off with Hydrogen & Helium"
Hydrogen (H) & helium (He) make up (basically) all of the Universe's mass (75% & 23% of it, respectively); after all, it's the nuclear fusion of H into He that powers the vast majority of stars illuminating the cosmos. On Earth, however, H & He are only a small part of the our planet (by mass, both combined make up far less than 1% of the Earth) [SB, 2013].
Even if we restrict it to the Earth's crust (part of the Lithosphere), H & He are still just a tiny percentage compared to the other, heavier elements, which were formed in generations of stars resulting, when heavier elements became abundant enough, in rocky planets [SB, 2013].
Figure 1 shows the abundance of elements in the universe & in Earth’s crust (thickness of about 100 km), while Figure 2 shows the chemical composition of the bulk Earth: iron is, by mass, the most common element on Earth, and the 6th most common element in the Earth's crust, being mainly deposited by meteorites in its metallic state, with its ores also being found there.
Figure 3 shows the chemical composition of the atmosphere (3/4 of its mass is within about 11 km).
Figure 1: Abundance of elements in the (a) universe & (b) Earth’s crust (in atom percent)
Figure 2: Chemical composition of the bulk Earth
Figure 3: Chemical composition of the atmosphere