Jarrod Dall's Photo Gallery
Vog in shoshonite porphyry boulder at base of cliffs
Specimen collected at North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows. Four distinct levels of shoshonite porphyry lava flows are distributed throughout the mesa resting upon and between upper layers of Denver Formation sedimentary rock deposits. Of the four lava flows present on North Table Mountain, Flow 3 is perhaps the most extensive forming the majority of the upper cap rock at a depth of 24m on the northeast portion of the mesa and thinning slightly towards the south (Drewes, 2008). At the southeast portion of North Table Mountain, lies a former rock quarry where Flow 3 forms large cliffs of shoshonite porphyry with small phenocrysts of plagioclase, pyroxene and olivine. Towards the top 6-9m of Flow 3 in the southeast quarry, an amygdaloidal zone exists where zeolite amygdules have formed in the gas cavities of the volcanic rock.
Zeolite mineral specimens present in vog include mesolite occuring as semi-radiating tufts of fibrous crystals associated with analcime, chabazite, stilbite, thompsonite, chrysocolla
Vog in shoshonite porphyry boulder at base of cliffs
Specimen collected at North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows. Four distinct levels of shoshonite porphyry lava flows are distributed throughout the mesa resting upon and between upper layers of Denver Formation sedimentary rock deposits. Of the four lava flows present on North Table Mountain, Flow 3 is perhaps the most extensive forming the majority of the upper cap rock at a depth of 24m on the northeast portion of the mesa and thinning slightly towards the south (Drewes, 2008). At the southeast portion of North Table Mountain, lies a former rock quarry where Flow 3 forms large cliffs of shoshonite porphyry with small phenocrysts of plagioclase, pyroxene and olivine. Towards the top 6-9m of Flow 3 in the southeast quarry, an amygdaloidal zone exists where zeolite amygdules have formed in the gas cavities of the volcanic rock.
View of cliffs at quarry
North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows. Four distinct levels of shoshonite porphyry lava flows are distributed throughout the mesa resting upon and between upper layers of Denver Formation sedimentary rock deposits. Of the four lava flows present on North Table Mountain, Flow 3 is perhaps the most extensive forming the majority of the upper cap rock at a depth of 24m on the northeast portion of the mesa and thinning slightly towards the south (Drewes, 2008). At the southeast portion of North Table Mountain, lies a former rock quarry where Flow 3 forms large cliffs of shoshonite porphyry with small phenocrysts of plagioclase, pyroxene and olivine. Towards the top 6-9m of Flow 3 in the southeast quarry, an amygdaloidal zone exists where zeolite amygdules have formed in the gas cavities of the volcanic rock.
MJU-1WWMesolite Na2Ca2Si9Al6O30·8H2O , Analcime Na(AlSi2O6)·H2O , Chabazite, Stilbite Subgroup M6-7[Al8-9Si27-28O72]·nH2O
Dimensions: 55 mm x 30 mm x 35 mm
Zeolites, Mesolite, Analcime, Chabazite, Stilbite on Shoshonite Porphyry
Size: 55x30x35mm
Specimen collected at North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows. Four distinct levels of shoshonite porphyry lava flows are distributed throughout the mesa resting upon and between upper layers of Denver Formation sedimentary rock deposits. Of the four lava flows present on North Table Mountain, Flow 3 is perhaps the most extensive forming the majority of the upper cap rock at a depth of 24m on the northeast portion of the mesa and thinning slightly towards the south (Drewes, 2008). At the southeast portion of North Table Mountain, lies a former rock quarry where Flow 3 forms large cliffs of shoshonite porphyry with small phenocrysts of plagioclase, pyroxene and olivine. Towards the top 6-9m of Flow 3 in the southeast quarry, an amygdaloidal zone exists where zeolite amygdules have formed in the gas cavities of the volcanic rock.
Mesolite occurs as loosely matted, semi-radiating tufts of fibrous crystals (Kile and Modreski, 1988). Analcime occurs as euhedral and semi-euhedral white trapezohedron crystals. Stilbite in euhedral crystal habit, transparent and colorless with pointed pseudo-orthorhombic shape up to 8mm and resemble thick thompsonite blades (Kile and Modreski, 1988). Chabazite occurs as flesh to pink colored crust of Pseudo-rhombohedron, commonly twinned along several different planes or axes (Tschernich, 1992).
6UP-QC1Mesolite Na2Ca2Si9Al6O30·8H2O , Chabazite, Stilbite Subgroup M6-7[Al8-9Si27-28O72]·nH2O
Dimensions: 90 mm x 73 mm x 30 mm
Zeolites, Mesolite, Chabazite, Stilbite on Shoshonite Porphyry
Size: 90x73x30mm
Specimen collected at North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows. Four distinct levels of shoshonite porphyry lava flows are distributed throughout the mesa resting upon and between upper layers of Denver Formation sedimentary rock deposits. Of the four lava flows present on North Table Mountain, Flow 3 is perhaps the most extensive forming the majority of the upper cap rock at a depth of 24m on the northeast portion of the mesa and thinning slightly towards the south (Drewes, 2008). At the southeast portion of North Table Mountain, lies a former rock quarry where Flow 3 forms large cliffs of shoshonite porphyry with small phenocrysts of plagioclase, pyroxene and olivine. Towards the top 6-9m of Flow 3 in the southeast quarry, an amygdaloidal zone exists where zeolite amygdules have formed in the gas cavities of the volcanic rock.
Mesolite occurs as loosely matted, semi-radiating tufts of fibrous crystals (Kile and Modreski, 1988). Stilbite in euhedral crystal habit, transparent and colorless with pointed pseudo-orthorhombic shape up to 8mm and resemble thick thompsonite blades (Kile and Modreski, 1988). Chabazite occurs as flesh to pink colored crust of Pseudo-rhombohedron, commonly twinned along several different planes or axes (Tschernich, 1992).
GGN-31TMesolite Na2Ca2Si9Al6O30·8H2O , Chabazite, Stilbite Subgroup M6-7[Al8-9Si27-28O72]·nH2O
Dimensions: 140 mm x 45 mm x 55 mm
Zeolites, Mesolite, Chabazite, Stilbite on Shoshonite Porphyry
Size: 140x45x55mm
Specimen collected at North Table Mountain, a mesa just west of Denver, Colorado, characterized by its basaltic cap rock formed from tertiary lava flows.
Mesolite occurs as loosely matted, semi-radiating tufts of fibrous crystals (Kile and Modreski, 1988). Stilbite in euhedral crystal habit, transparent and colorless with pointed pseudo-orthorhombic shape up to 8mm and resemble thick thompsonite blades (Kile and Modreski, 1988). Chabazite occurs as flesh to pink colored crust of Pseudo-rhombohedron, commonly twinned along several different planes or axes (Tschernich, 1992).
