Hi Susan:
You are referring to what is called hand-held XRF or p-XRF (portable). XRF is X-ray fluorescence. These units come in basically two types:
1. All manufacturers provide systems based on sophisticated programming called "fundamental parameters" and are splendid devices for homogeneous material (i.e ceramic) and alloy identification. This is by far the largest market.
2. Bruker also manufactures a unique system called the Tracer which is common in the art/artifact/archaeology sector because it is well suited to the unknown compositions and heterogeneous nature of the samples/specimens. One of its standard calibrations is for sourcing obsidian.
Scott McGeorge
Transition Technologies
-----Original Message-----
From: HISTORICAL ARCHAEOLOGY [mailto:[log in to unmask]] On Behalf Of Susan Walter
Sent: 21-Mar-15 13:16
To: [log in to unmask]
Subject: I'm brain dead need help
Years ago I plunked a ring into a machine that analyzed its chemistry. There were expensive models and those you could take into the field. I remember it as “Xchrom” but that’s not coming up in my feeble internet searching strategies. Can someone help me please? What is that thing called?