Picture Jasper 

• picture jasper, landscape jasper, chalcedony (kal-SED-uh-nee) is microcrystalline or cryptocrystalline quartz; hexagonal (trigonal) crystal system; chemical composition SiO2
• natural material no any treatment
• opaque 
• brown color with appearance landscape scene
• landscape agate, picture agate, fortification agate, etc – chalcedony with colored patterns resembling a landscape, etc. We always use “Jasper” to call this material in business industry.

Identification

• Refractive Index: 1.535-1.539; 1.53 or 1.54 spot reading
• Birefringence: usually not detectable, but may show .004
• Pleochroism: none 
• Specific Gravity: 2.60 (+.10,-.05)
• Polish Luster: greasy to vitreous
• Fracture: conchoidal; sometimes granular
• Luster: dull to waxy
• Cleavage: none
• Hardness: 6 ½  to 7
• Toughness: good

Sources: South Africa

 

Stone information is reference from

Gem Reference Guide, Published by GIA. ISBN 0-87311-019-6

Gemstones of the World, Published by Sterling Publishing Co., Inc NY, ISBN 1-4027-4016-6

Encyclopedia of GEMSTONE, Published by ISHINSHA CO., LTD. ISBN 978-986-251-831-1