Jade in Chinese, where it originated, is said, “Yu.” Jade comes in many colors; the many nuances of green, white or pink, red, black, yellow, orange, browns and delicate violet tones. In America the most popular colors of Jade are Spinach green and apple green.
There is jade, jadeite/jadite or nephrite to distinguish between. Jade with rare colors like white or pink, red, blacks, browns and violets are the most expensive. Jadeite or jadite, which are the same items(for the purpose of these notes we will use jadeite.) Jadeite is more precious than nephrite.
#1 Become familiar with real jade
#2 Become familiar with imitations like; New Zealand greenstone, Serpentine (New Jade), Chrysoprase (Australian Jade), and others
#3 Check the feel, Jade is very dense and it should feel heavier than it looks. It should feel cold, smooth and somewhat soap like in your hand.
#4 Hold it up to the light and/or inspect with a 10X loupe it should look fibrous or granular, felt-like, or asbestos-like inter-twining. Look for intense color, texture, clarity and transparency.
#5 Do a scratch test. (Be cautious this can damage items.) Jade will scratch glass, metal and steel.
#6 Tap stones together, if it sounds like a plastic bead, it is probably fake; if it makes a deeper more resonant sound it might be authentic.
Get out there and see if you can find some genuine Jade items! :)