May the Quartz be with you

Dating amber alone is risky – always bring a chaperon.

In this case the strata and rocks in which Dominican amber is found.

Anyone familiar with the previous newsletter will remember that amber was deposited in dirt and sand at the bottom of lagoons as copal.

Hence this dirt and sand is organic rich and contains forms of microfossils – fish teeth, oysters, corals, mollusks, tiny crustaceans – that can help in verifying the age.

And it is thanks to much of these microfossils that we say 20 million years, the Early Miocene period, independent from the amber.

And, yes, you guessed it: there is yet another problem.

The dirt in which Dominican amber is found differs from site to site all over the island.

Sedimentary RockGenerally we are dealing with clastic sedimentary rocks composed largely of quartz with other common minerals including feldspars, amphiboles, clay minerals, and sometimes more exotic igneous and metamorphic minerals such as slate, schist or gneiss.

But exactly that causes difficulties because sometimes there aren’t any or not enough microfossils to go by and the different rocks and minerals are from time periods older or younger than previously assumed.

That makes correct dating a real stumper.

Schist happens.