CompuServe Messages

>> few quartz crystal Keokuk geodes which were formed in cavities in a limestone in Illinois and Iowa.<< Did these have generally uniform bands all around or were they more horizontal or a combination? >>formed as Silicate fills of gas cavities in a lava which subsequently decomposed.>> Seams odd the lava would decompose leaving the quartz. I have discovered a lot of quartz gravel has imprints of shells, sometimes the shells are enclosed within quartz and the body parts replaced by quartz. I downloaded a Surveyor 1 picture that has what looks like a Kritosarus. Maybe you could identify. Krit.gif lib 12 Kamron