In 1791 William Gregor discovered an unknown element in the mineral Ilmenite. In 1795 Martin Heinrich Klaproth rediscovered the element, this time in Rutile ore and called it titanium after the Titans of Greek mythology. As the metal easily reacts on oxygen and carbon at high temperatures, is it difficult to produce pure titanium. In 1922 Anton Eduard van Arkel succeeded  in preparing pure metallic titanium (source Wikipedia ).

Around the 50's, people were going to use titanium for industrial purposes such as aviation and space because of its unique toughness versus weight ratio, the medical world uses it for prostheses because it is 100% allergy free. In the shipbuilding industry they use it for propellers because of the good resistance to salt water. Since 1975 it is used for jewelry.

It is one of the hardest natural metals. It is a very light and strong metal. It has a white silvery gray color. Titanium can also turn to other colors by heating, this is just not ideal, it is better to give the titanium a chemical treatment of the oxide layer, this is called anodizing.

Rutile and Ilmenite are the titanium minerals from which titanium is extracted. This is mainly found in rocks, sand rock and heavy mineral sands.

Titanium is mined in Australia, Russia, New Zealand, Norway, Canada, Malaysia and South Africa. Also on the moon is a high content of titanium.

Titanium is ideal for jewelry because the metal has a very light weight. Moreover, titanium is very skin friendly and causes no allergic reaction. It is nickel free. The jewelry rapidly adapts to the temperature of the body area so it does not feel cold when it gets in contact with the skin.

Titanium has the ability to recover by itself. Minor damage will be surrounded by a “coating” which will form by an oxidation process, therefore will not be visible.

Titanium Composition: 
Titanium grade 1 is pure titanium. Here you can see the chemical composition. 
C 0.10 max (carbon)
Fe 0.20 max (iron)
H 0.015 max ( hydrogen)
N 0.03 max (nitrogen)
O 0.18 max (oxygen)
Ti Remaining (titanium)

Titanium grade 2 is also pure titanium. Here you can see the chemical composition.  
C 0.10 max (carbon)
Fe 0.30 max (iron)
H 0.015 max (hydrogen)
N 0.03 max (nitrogen)
O 0.25 max (oxygen)
Ti Remaining (titanium)

Titanium grade 23 has by adding aluminum and vanadium improved ductility and fracture toughness with some reduction in strength.
AI 5.5-6.75 max (aluminum)
C 0.10 max (carbon)
Fe 0.40 max (iron)
H 0.015 max (hydrogen)
N 0.05 max (nitrogen)
O 0.13 max (oxygen)
Ti Remaining (titanium)
V 3.5-4.5 (vanadium)