Nummulites
Some large #forminifera from France (Eocene age) at #MuseuGeologico in #Lisbon. Forams are usually microscopic phytoplankton; these Nummulites are visible to the naked eye, the ones at the front must be 15mm in diameter.
Shark tooth
This 90mm (root to tip) serrated shark tooth would have taken a chunk out of its prey (no 4, at rear). But of course, the owner would have had a mouthful of them. #MuseuGeologico in #Lisbon
Single crystal of Beryl showing well developed hexagonal prisms
Mass of Wolframite
Two large mineral samples from the #MuseuGeologico in #Lisbon. A large (500x300mm) single crystal of Beryl (beryllium) and a large lump of Wolframite (tungsten) c700x500mm.
Guide to major crinoid structural units (in Portuguese). nb These are marine animals, not plants, which secrete a calcareous (chalky) exoskeleton.
Slab chuc-a-block with crinoid pieces. Apologies for camera shadow, lower left.
With this handy general guide to #crinoid (echinoderm) morphology, you should be able to navigate your way around this 600x600mm slab of them, at the #MuseuGeologico in #Lisbon
Cruziana
It’s fossil, er Wednesday, and we’re in the #MuseuGeologico in #Lisbon looking at an 800x800mm slab (underside) of Cruziana trace fossils. When you get up close you can see the individual scratch marks from the #trilobite biramous appendages.
Translucent sheet of muscovite mica
“Nodular” habit of biotite mica in an unusual granite - yes, granite.
. #MuseuGeologico in #Lisbon is small but perfectly formed. Contrasting exhibits of #biotite and #musovite micas: muscovite as a translucent sheet c 250x250mm, biotite - wait for it - in discrete nodules within an unusual form of granite, which spall off in lumps as they’re weathered out.
Museuo Geologico in Lisbon
Always a challenge to make an exhibit both accessible and engaging but #MuseuGeologico in #Lisbon has made a good stab at it. Fossils arranged by location within the marine environments and distinguished by age by colour of label background. Pic doesn’t do it justice.
