Question: What are some of the rare materials on Earth that are needed for life?
About the article "Biochemistry", section "Starting materials: the chemical elements of life".

Candidate passages:
The hypothesis concludes, more or less, that complex life is rare because it can evolve only on the surface of an Earth-like planet or on a suitable satellite of a planet.
Some biologists, such as Jack Cohen, believe this assumption too restrictive and unimaginative; they see it as a form of circular reasoning.
According to David Darling, the Rare Earth hypothesis is neither hypothesis nor prediction, but merely a description of how life arose on Earth.
In his view Ward and Brownlee have done nothing more than select the factors that best suit their case.
What matters is not whether there's anything unusual about the Earth; there's going to be something idiosyncratic about every planet in space.
What matters is whether any of Earth's circumstances are not only unusual but also essential for complex life.
So far we've seen nothing to suggest there is.
Critics also point to a link between the Rare Earth Hypothesis and the creationist ideas of intelligent design. 
Around two dozen of the 92 naturally occurring chemical elements are essential to various kinds of biological life.
Most rare elements on Earth are not needed by life (exceptions being selenium and iodine), while a few common ones (aluminum and titanium) are not used.
Most organisms share element needs, but there are a few differences between plants and animals.
For example ocean algae use bromine but land plants and animals seem to need none.
All animals require sodium, but some plants do not.
Plants need boron and silicon, but animals may not (or may need ultra-small amounts).
Just six elements—carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus—make up almost 99% of the mass of a human body (see composition of the human body for a complete list).
In addition to the six major elements that compose most of the human body, humans require smaller amounts of possibly 18 more.
Earth materials is a general term that includes minerals, rocks, soil and water.
These are the naturally occurring materials found on Earth that constitute the raw materials upon which our global society exists.
Earth materials are vital resources that provide the basic components for life, agriculture and industry.
Earth materials can also include metals and precious rocks. 
Large tank trucks are used for example to transport gasoline to filling stations.
They also transport a wide variety of liquid goods such as concrete, milk, water, gasoline, diesel, and industrial chemicals.
Tank trucks are constructed of various materials depending on what products they are hauling.
These materials include aluminum, carbon steel, stainless steel, and fiberglass reinforced plastic (FRP).
Some tank trucks are able to carry multiple products at once due to compartmentation of the tank into 2, 3, 4, 5, 6 or in some rare cases more tank compartments.
This allows for an increased number of delivery options.
These trucks are commonly used to carry different grades of gasoline to service stations to carry all products needed in one trip. 
There is an impending increase in the costs of many rare materials used in the manufacture of hybrid cars.
For example, the rare earth element dysprosium is required to fabricate many of the advanced electric motors and battery systems in hybrid propulsion systems.
Neodymium is another rare earth metal which is a crucial ingredient in high-strength magnets that are found in permanent magnet electric motors.
Nearly all the rare earth elements in the world come from China, and many analysts believe that an overall increase in Chinese electronics manufacturing will consume this entire supply by 2012.
In addition, export quotas on Chinese rare earth elements have resulted in an unknown amount of supply.
A few non-Chinese sources such as the advanced Hoidas Lake project in northern Canada as well as Mount Weld in Australia are currently under development; however, the barriers to entry are high and require years to go online.