Independent Diamond Laboratories
ABN
34 005 948 185
Observation and Analysis
Observation
All IDL observers are experienced in identifying heavy
minerals. IDL provides a high quality mineral
observation service at affordible rates. We specialise
in identifying all diamond indicator minerals. To learn more
about our services for non-diamond indicators please contact
IDL.
Analysis
IDL's standard
procedure is to have all observed samples checked by a
mineralogist.
Analytical
services include:
1. Microscopic
assessment of kimberlitic affinity and grain wear.
Comparison of electron microbrobe data and morphology
of kimberlite indicators to assess diamond affinity.
2. Advice for
further work.
3.
Identification of other types of economic
mineralization.
Chrome Spinel Analysis for Kimberlite Affinity
Chrome spinel is an excellent pathfinder
mineral for diamond exploration. The low hardness of
chromite also gives a good measure of distance from
source in an alluvial system. Unfortunately, it is
also a common mineral in many types of rock.
Routine probe
analysis of chrome spinel without prior morphology
assessment destroys more than 50% of the data
available. If the explorer is faced with background
chromite the eye is far cheaper, faster and more
discriminatory first line of attack than the electron
microprobe. Chromite derived from kimberlite has a
distinctive appearance which can only be recognized
through experience. Chromite studies are a combination
of chemistry and appearance, each of equal weight.
Dependence on
chemistry to determine diamond affinity may also be
unreliable as high chrome (>60%Cr2O3) grains are
susceptible to breakage. The best chromite are the
ones you do not see if your indicator minerals have
been subjected to abrasion or impact.
Kimberlitic
Chromite