Raynaud's syndrome can cause this. It is strongly advised that you see a doctor/research online as well, as this can be remedied with simple applications but may also be indicative of a more serious condition (autoimmune).
Your finger turns the colour white after being in the cold because the blood circulation in your finger slows down to warm up the rest of your body. hence the white color.
it will cold
7u die
loss of thermal energy from your finger.
if your hamsters nose pink to white that means its to warm or cold feel them if they are hot or cold
Without knowing more details could be many causes. Is this a chronic condition? Could be Raynaud's phenomenonhttp://www.answers.com/raynauds or combination of other related circulatory problems such as arthritis, polymyositis, carpal tunnel, drugs, exposure to cold, lupus etc. etc.
Because it's so cold outside the equator that it freezes the skin so it turns white but when it gets unfrozen it turns black again.
finger foods are delucious and hot or cold
Incorrect pipe size installations
salty water turns cold with vinegar.
If the beaker has a cold water, or something else cold, in it than the heat that is in our finger will run out of you finger into the cold water. This leaves your finger 'empty' of heat, giving you the sensation of being cold. You need to remember that only heat moves. When you are cold you wear a jumper that keeps the heat in your body, not keep the cool out.
Most arctic mammals show this behavior eg. arctic fox .