Where: Northern Ireland · Europe · approx. 55.21, -6.65 (vicinity only)
Why this spot: Lower Jurassic (Lias) baked by dolerite (Portrush Rock)
What turns up: Ammonites in the hard 'Portrush Rock' hornfels, plus zeolites and calcite in the dolerite
Access: Gray area.
The Portrush Sill is an ASSI; loose foreshore collecting tolerated, no hammering the protected rock, historic 'basalt controversy' site.
Open in Mudlark Map →
Satellite view, historic-map overlays, tide/flow context and field notes are in the app. Exact research detail is part of Pro.
Pins are approximate by design. This page is historical research, not permission to dig. Check ownership and local law first.