Precious metals are rare, naturally occurring metallic chemical elements. They tend to be less reactive than most elements, are usually ductile and have a high lustre. Precious metals have high economic value. Examples are: gold,silver and platinum. Gems on the other hand are minerals or rocks that can be cut, shaped, and polished into beautiful stones. Examples include emerald, ruby and sapphire.
Both precious metals and gems are rare and valuable.
Answer:
1) Climate change in the last 100 Myr. has been extreme, thus offering a potential explanation of Earth's <u>TRUE</u>
Explanation:
2) Orbital forcing (changes in Earth's axis tilt) are too insignificant in the last 25,000 yrs. to explain Earth's warming in the past 125 years. <u>FALSE</u>
3) Retreat of glaciers in the past 8000 years has been uniform, thus potentially explaining Earth's warming in the past 125 years. <u>FALSE</u>
<u>Erosional deformation
</u> is not a form of rock deformation.
Answer: Option B
<u>Explanation:</u>
Rocks are all the time being subjected to force within the surface of earth because of which these rocks tend to twist, bend or get fractured. This causes the rock to change in their shape or size which is known as the deformation of rock and this deformation is affected by temperature, rock type, time and the pressure. Rocks deform in two ways which are ductile and brittle deformation.
