The Jewel Mountains were a mountain range located on the continent of Lurvan on the planet Krypton. It was situated North-northwest of the capitol city of Kandor and was bordered by the Cogo Sea to the North and the Scarlet Jungle Fire-Falls to the South. The mountains were formed by the fossilized remains of large prehistoric birds millions of years ago.
Several centuries ago, the alien invaders known as the Vrangs enslaved the population of Krypton and put them to work mining minerals in the Jewel Mountains. This continued for several years until a courageous slave named Hatu-El led a revolt that overthrew the Vrang warlords. The Jewel Mountains were destroyed when geothermic upheaval caused the planet Krypton to explode. 
Years after Krypton's destruction, the Phantom Zone criminal Jax-Ur traveled backwards into the past where he performed experiments on select crystals transforming into what would eventually become known as Jewel Kryptonite. Jewel Kryptonite possesses the ability to channel the mental energy of beings trapped in the Phantom Zone. 
- Although the existence of the Jewel Mountains may still be a part of modern DC Comics continuity, the history surrounding this landmark is exclusive to the continuity of Pre-Crisis Krypton.