Why did Lead II nitrate and potassium iodide turn yellow?

Lead iodide can be obtained as a yellow precipitate by reacting solutions oflead(II) nitrate and potassium iodide the other compound created by the reaction is potassium nitrate which is a white power but as it is soluble it does not form a precipitate.

2KI + Pb(NO3)2 --> 2KNO3 + PbI2

the balanced equation if you were needing it