Modern L100 coins dated 1954 and later were struck in a stainless-steel alloy called "Acmonital".
If your coin is earlier than that, please post a new, separate question with its date. Without that information it's not possible to give a specific answer.
No, it is made of stainless steel.
No. Lire are not worth anything it is no longer used or made. Italy uses the Euro.
If I read your question correctly the bracelet is made from Italian lire coins and the chain is 10K. If these are real Lire the coins they are not gold, but that they could be set in a 10K coin holder to hold them to the chain. Often when coins are used in jewelry they are placed inside a frame/holder. My guess is that what you have.
The actual value of a 200 Lire Italian coin is technically nothing, since Italy now uses the Euro. In the 1970's when it was made, this was worth about forty US cents.
Metal and agreed upon concepts of ideas pertaining to exchange and currency.
If you're referring to Italian lire, Italy switched to euros in 2002 so the lire is now obsolete. At that time 500 lire were worth roughly half a U.S. dollar; you can get more accurate currency rates by going to the http://currate.com site. Also, you will see the Lire currency images on every currencies listed there.
According to en.ucoin.net/catalog, the small, silver-coloured 100 Lire coins minted for circulation in the Italian Republic were made apparently between 1955 and 1999 and are of stainless steel composition, but the website doesn't state whether any other metals are mixed in at low percentages. The coin may be 100% steel, or it may not be. I haven't been able to find that information. The Italian 50 Lire coin, recorded by the same website as minted between 1954 and 1999, is also listed as stainless steel. Both the L.50 and L.100 coins were in circulation (use as payment) until 2001.
Lire were made obsolete in 2002 when Italy adopted the euro. At that time 200 lire would have been worth less than 15 cents.
There were four different 1943 issues of the 100 Lira note by the Banca D'Italia. In good used condition, they are worth $8-$25. The rarest version, in mint uncirculated condition, is worth as much as $300.
The 1957 20 Lire coin from Italy (KM# 97.1), of which 60,075,000 were produced, is made of Aluminum-Bronze, weighs 3.6000 grams, and measures 21.25 mm in diameter. According to the Standard Catalog of World Coins, an example is worth US$0.20 in Fine condition, US$0.40 in Very Fine condition, US$2.00 in Extremely Fine condition, and US$10.00 in Uncirculated condition.
Lira is an obsolete monetary unit, as Italy is on the Euro system. Obviously coins made under the Lira or lire ( plural) denominations have some collector value. in the case of the l9ll Battleship coins- honoring the fiftieth anniversary of the Royal Italian Navy, these were done in both Silver and Gold and are very rare. The Gold Battleship coin was struck in both 50 and l00 Lire sizes.
The coin is so common because so many were made, it's likely face value.