Costa Rican Copal "A" (Sandstone Deposits, Indeterminate Age [~2.58 Ma-Recent])

Costa Rican Copal
Quepos Canton, Puntarenas Province
Sandstone Deposits
Paso Real Fm./Brujo Fm. (~2.58 Ma-Recent).

EDIT (3/26/2022): from further information I've recently received, the copal was recovered from a farmer's field in the Quepos canton, and was actually dislodged from its source via torrential rains, and not an earthquake. It's possible the copal was originally deposited in sandstones from the Cordillera de Talamanca to the north, and redeposited to the south where recent erosion then dislodged it.

After reviewing various publications, and comparing various Formations present in the Talamanca range on basis of age, general location, and composition, I feel confident in suggesting the copal came from sandstone layers belonging to the Paso Real Fm.: this Formation is Late Pliocene to Early Pleistocene in age, about 2.58 Ma. Other authors describe Costa Rican "resin" as about 160-100 years in age (Langenheim et. al. 1975), though as this copal is noticeably harder and less reactive to acetone than Colombian copal from deposits near Cerrejón, I do not feel the copal I have is quite that young: still, I will leave that possibility open.

Sources:
"Botanical origin of resin objects from aboriginal Costa Rica"; Vínculos; J. H. Langenheim, et. al. 1975

"Active thrusting in the inner forearc of an erosive convergent margin, Pacific coast, Costa Rica"; tectonics Vol. 23, Issue 2; Donald M. Fisher, et. al. 2004

"Stratigraphy, Sedimentology, and Geologic Evolution of Eastern Terraba Trough, Southwestern Costa Rica (Tectonics, Forearc Basin); LSU Historical Dissertations and Theses; Peter B. Yuan 1984

https://en.wikipedia.org/wiki/List_of_fossiliferous_stratigraphic_units_in_Central_America#Costa_Rica