HGTR-KTP: High Gray Track Resistance (HGTR) KTP for CW and high average power SHG HGTR KTP crystals have gray track resistance sufficiently greater that typical flux grown KTP. This is possible due to advances in the controlled growth of KTP crystals using proprietary modified fluxes and heat treatment. These HGTR KTP crystals are suitable for high power density applications where regular flux-grown KTP crystals would suffer from gray track damage.