Quartz w/ petroleum inclusions

This is a pair of double terminated Quartz crystals from Zhob Baluchistan: a war torn region of Pakistan. One is filled with petroleum, and considered a four phase included Quartz. The second is a clear example of a three phase included Quartz. It has a fluid inclusion (not petroleum) and trapped gas bubble. The first pic is normal lighting of the pair, and the second pic is both of them under long wave fluorescent light. These two make a great set to show off fluorescence.  The gas bubble forms when the the Quartz cools after forming, the petroleum contracts more than the Quartz because it is less dense, it pulls a vacume within the fluid thus creating a "gas" bubble.  The four phases are: the gas bubble trapped in the petroleum, the petroleum itself, a darker brown previously organic material, and black carbon inclusions. I learned this from an insightful geologist who specializes in Quartz inclusions, whom I met at the Tucson Main show. 

The petroleum included Quartz is in good condition with smaller quartz crystals growing on it, and a few spots of contact where some of those came off. the clear crystal is also in good condition with just a little minor chipping on the bottom edge of one termination.