Geodes in Kentucky

[Stephen Rowley <srowley@xxxxxxxxxxxxxx>]

If it is the spherical sparkly kind of geode you want - then the best
bet is to find an importer/dealer.  These are formed by hydrothermal
mineralisation in certain kinds of volcanic lava fields.  Best collected
where the rock is being rapidly eroded, like on the coast. A lot of the
geodes on the market are exported from Central and South America.

You can buy them uncut quite cheaply.  However, many are uninteresting
once opened, so you have to buy a good number to be sure of getting
something worth looking at.

I used to buy them by the sackful when I worked in a lab, then cut them
on a diamond saw and polish them on a lap wheel.  Still have a couple of
nice ones around.  I remember all my relatives had geodes for Christmas
one year, then then I changed jobs.

Impressive crystal lined structures can also be found in sedimentary
rocks where mineralisation has occurred.

I would encourage any stone carver to take an interest in geology.  It
helps when selecting stone.  Many geological descriptive terms for stone
were originally masons terms.  Also names of particular strata often
reflect their workability.  I live on a limestone known as the 'Inferior
Oolite'  so called because it was not as good for building as the
'Superior Oolite'.  It is too crumbly for fine detail.  So, not much
good for carving. Still it makes for some attractive houses of the
vernacular kind.

Regards

Strolls
(Sculptor and geologist)

daniel andrade wrote: