is the sapphire ring precious? How is it precious?

Answer 1

First of all the term "semi-precious" is no longer accepted by the world gem and jewellery classification organizations and should not be used for any stone. Secondly blue sapphire is one of the traditional 5 major gems - Diamond, Ruby, Sapphire, Emerald and Pearl (although pearl is organic it is there by historical use).
As to the value of your ring it is impossible to even make an educated guess without seeing it. Like all gemstones sapphire price is judged on its colour, clarity, carat weight and cutting. A super fine sapphire sold some ten years ago for $2,828,546 ($45,607 per carat) which, I am sure you will agree, is hardly semi anything. Of course your ring will not be in this class, sapphires can be tiny - 100 to a carat - and they can be very poor quality as well so I recommend you take it to a reputable jeweller and get it valued.
As a P.S. I would like to add that I wish people who clearly know nothing about a subject other than reading unreliable articles on the net (Wikipedia being a notable offender with unreliable articles) would not give answers as if they were experts.

Answer 2

A sapphire ring is classified as a semi-precious stone. While I do not know what the difference between semi-precious and precious is I bet that it has something to do with it's value for example a precious stone, such as diamond, is worth more than a semi-precious stone such as an emerald.

Answer 3

Sapphire is not very expensive and is considered a semiprecious gem. A big nicely formed one with good figure (star sapphire) can be worth hundeds of dollars.
In the first answer, nothing is wrong with the main part, but emerald, like ruby, is a precious stone, not semi.
http://socrates.berkeley.edu/~eps2/
http://www.minerals-n-more.com/loose_stones.html
http://en.wikipedia.org/wiki/Gemstone