BRN 9-3 - Flipbook - Page 72
Chemically, the difference between
copal and amber is the amount of
polymerization which has occurred
and the loss of volatile oils (terpenes).
When I smelled the Pi–on Pine resin
nodules I found I could easily detect
that Òpine smellÓ. That smell comes
from the volatile oils in resin. These
oils are lost in the journey from resin
to amber - so you can smell amber all
day and not detect that Òpine smellÓ.
The molecular transformation which
happens along the way is signiÞcant
and alters the physical characteristics
of the material. You can see the
difference between resin, copal, and
amber. Copal and my pine nodules
are beautiful but they lack that
translucent radiance of amber. If I
were to look at them under an ultraviolet light there would be no (or very
little) ßuorescence. If they had made
their journey to become amber they
would ßuoresces pale blue or green.
They would also have a higher
melting point (200¡C - 380¡C) versus
something less than 150¡C for copal.
Amber is completely fossilized and is
resistant to organic solvents while
copal is semi-fossilized and will
become sticky, or even dissolve, in
acetone.
See footnote 3 for a discussion of the
resin-copal-amber deÞnitions. Note
that, if you are linguistically inclined,
the matter is complicated by the fact
that copal derives from the word
copalli in N‡huatl. In that language of
the Aztecs the term means resin recently formed resin.
So, following Sol—rzano-Kraemer et
al. (2020)2,3 the stuff I found under a
Pi–on Pine is Òdefaunation resinÓ.
That is a term destined to smother any
sense of romance associated with
leaning up against a pine when you
are tired.
creature is maintained in Þne detail,
very Þne detail. A work of art. On the
following page, there are several
examples of copal with insect and
other organic inclusions. On their way
to becoming amber - or at least they
were before they were collected.
As strange as it may seem, this rabbit
hole seems to be leading to an answer
to the question and thought
experiment I formulated under the
Pi–on Pine. The more I delve into the
matter, the active external force
involved in polymerization seems not
to be pressure but rather thermal
action. It is heat. Now, pressure is
often used to generate heat, I will
grant that, but they are not the same.
Strictly from a chemical perspective
this makes sense: heat drives many
chemical reactions. Pressure, in most
cases, is also an indication that the
specimen has been effectively
sequestered from the atmosphere but that may make it more difÞcult for
the terpenes to escape.
If you have the chance to lean up
against a pine sometime soon, look
around for bits of pre-amber and
marvel at what it might become in a
few million years, if thousands of
things go right for it along the way.
Furthermore, Sol—rzano-Kraemer et al.
(2020)2 note that Òsome resins have
the property of polymerizing quite
quickly, e.g., Hymenaea spp. resin can
harden within daysÓ, clearly (I posit)
the result of chemical action and
without pressure.
Saitta and Kaye (2025)4 note that
ÒLight microscopy suggests that
matured resin dries, possibly hardens,
and darkens into a brittle, yellowÐ
orangeÐbrown translucent mass with
increased luster, exhibiting ßow lines,
birefringence, conchoidal fracturing,
and air pockets typical of copal/
amber.Ó They report on their
experiments with artiÞcially induced
maturation in resins. They used
pressure to allow for ÒcontrolledÓ
higher temperatures to accelerate the
maturation process.
In the end, my understanding of the
pre-amber to amber transition was
enhanced a bit. Somehow not very
satisfying, but noticeable.
In most fossil specimens the fossil was
created by a mineralized replacement
process. The organic material of the
creature was replaced with a mineral
of some type. Sometimes this process
results in crude, broad-stroke fossils
which look like the original but do not
have much detail. Sometimes the
detail can be very Þne. In the
formation of amber, the fossilized
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________________
1. Ken Anderson, R. E. Winans, and R.
E. Botto, ÒThe Nature and fate of
natural resins in the geosphere - II.
IdentiÞcation, classiÞcation and
nomenclature of resinitesÓ,
Organic Geochemistry, Volume 18,
Number 6, pp. 829-841, 1992.
2. Sol—rzano-Kraemer, M.M., Delcl˜s,
X., Engel, M.S. et al., Ò A revised
deÞnition for copal and its
signiÞcance for palaeontological
and Anthropocene biodiversityloss studiesÓ, ScientiÞc Reports, 10,
19904 (2020). https://doi.org/
10.1038/s41598-020-76808-6
3. The abstract from Ò2Ó above adds
signiÞcantly to the deÞnitions
associated with ÒamberÓ, ÒcopalÓ,
and ÒresinÓ. It reads:
ÒThe early fossilization steps of
natural resins and associated
terminology are a subject of
constant debate. Copal and resin
are archives of palaeontological
and historical information, and
their study is critical to the
discovery of new and/or recently
extinct species and to trace
changes in forests during the
Holocene. For such studies, a
clear, suitable deÞnition for copal
is vital and is herein established.
We propose an age range for copal
(2.58 MaÑ1760 AD), including
Pleistocene and Holocene copals,
and the novel term "Defaunation
resin", deÞned as resin produced
after the commencement of the
Industrial Revolution. Defaunation
resin is differentiated from
Holocene copal as it was produced
during a period of intense human
transformative activities.
Additionally, the ÔLatest Amber
Bioinclusions GapÕ (LABG) since
the late Miocene to the end of the
Pleistocene is hereby newly
