KEPR learned this is part of a natural patination. In the same way the Statue of Liberty turned green, the dome will one day be green as well.
The dome was originally tin, but copper was added in an expensive restoration a decade ago.
That cost $11 million, compared to the $82,000 it cost to build the courthouse originally. That was back at the turn of the century, when only about 5,000 people lived in Pasco.