|This one is a flower garden - stretch your imagination people!|
|This is a swan...or maybe a tail-less brontosaurus?|
|And, voila! My finger recreated!|
Here it is: Steel with at least 10.5% of chromium are considered 'stainless' - which basically means corrosion resistance. A very thin chromium-rich oxide layer forms on the surface of the metal and it prevents rusting. Stainless steel (this part is so cool), if it is scratched, will 'self-repair' itself as a new oxide layer is formed. Whereas a scratch on other plated steels will often lead to corrosion. The more chromium, the stronger the corrosion resistance of the steel. And other metals are added to steel to give particular properties such as strength and malleability to it. Specifically nickel is used to strengthen the oxide layer. And it is the addition of nickel that is what changes the steel from magnetic to non-magnetic. This non-magnetic kind makes up about 70% of the production of stainless steel.
And generally that's how we check if something is steel or stainless steel - just by checking if it is magnetic.
Although, I did say most stainless steels are not magnetic. The 400 series of stainless steel is magnetic - have you ever heard of 410 Stainless Steel? The 400 series, as you probably guessed, doesn't have any nickel in it.
If you want to know even more about Stainless Steel & all it's interesting facets check out the Stainless Steel Information Center.