[meteorite-list] Streak'n

From: E. L. Jones <jonee_at_meteoritecentral.com>
Date: Thu Apr 22 10:17:43 2004
Message-ID: <3FD74E3B.30209_at_epix.net>

Great Idea Mark! The tank lid of an american standard toilet will also
work in a pinch--or so I've been told...(grin) The back of a floor tile
can be used also. Watch about using shards as they also can cut.

A good diagnostic streak is at least the size of a jumbo pencil lead.
Minerals which tend to show a streak are in the Oxide, Sulfide, or
Native(Elemental) class.

In this vein, silicates do not "streak", so for Olivine, Pyroxenes, and
Bronzite, etc-- typical matrix for Common Chondrites , the streak test
is a tool for exclusion.

There are also some powder tests and the borax bead test used in home
diagnostics.

If you google "streak test" there have been several web sites with the
how to and with a list of streak colors matched to minerals.

Elton

Mark Jackson wrote:

> David,
>
> Get a coffee cup out that has a white, unglazed mating ring on the
> bottom. Rub the rock vigorously along the ring (or vice versa may be
> easier)
> <http://pa.yahoo.com/*http://us.rd.yahoo.com/evt=21260/*http://photos.yahoo.com>
Received on Wed 10 Dec 2003 11:47:55 AM PST