Convert from carat [UK] to petagram

Unit Definition (carat [UK])
The carat [UK] is a unit of mass used for diamonds and other precious stones. In the U. S. and Britian, the diamond carat was formerly defined by law to be 3.2 troy grains, which is about 207 milligrams.

Unit Definition (petagram)
The petagram is a metric unit of mass equal to 10E15 grams or 1 gigatonne (one billion metric tons). This unit is used in atmospheric science and other scientific contexts where large masses are considered.