ROCKS and FOSSILS GALLERY

All of the specimens shown on this website are taken from my personal collection. Click on the thumbnails for more images.
(Note: mya = "million years ago")

> AMBER
Certain conifers and tropical trees secrete a sticky resin (containing aromatic organic compounds such as terpenes, alcohols, and esters) as a natural defense against wood-boring insects and other pests. Over time, the terpenes can become linked and polymerized as the resin eventually hardens to become fossilized amber. Along with general organic debris, amber also often contains within it such "biological inclusions" as entrapped insects and other invertebrates (gnats, ants, bees, wasps, flies, beetles, moths, spiders, and termites are very common; true mosquitoes are rare), botanical parts (flowers, leaves, bark, etc.), occasional mammal hairs, small feathers, and extremely rarely, small vertebrates such as frogs and lizards. Amber is worldwide in distribution, with different locations corresponding to distinct geological ages, but most commercially available amber is mined in the Dominican Republic and the Baltic region. The former, which contains a great abundance and diversity of inclusions, comes from the extinct leguminous tree Hymenaea protera - a relative of the pea - and has been dated from 15 to 40 mya, although the most recent research places it at about 20 mya. (Despite "Jurassic Park," this is clearly too recent to recover DNA from dinosaurs, who became extinct some 65 mya. The movie also incorrectly depicts the mines themselves; they are in reality long, hot, dark shafts, so narrow and cramped that they can accommodate only one worker at a time.) Amber also sustains an electrostatic charge (its name in ancient Greek is elektron), and has been used for centuries by many civilizations for its magical healing properties, as well as for currency, a preservative, and for the carving of exquisite figurines, amulets, and other magnificent works of art and jewelry. It also occurs in a variety of colors with suggestive names: "butterscotch," "cherry," and even "blue" amber; see below.


Extinct giant termite, Mastotermes electrodominicus, in Dominican amber (approx. 20 million years old) Mastotermes electrodominicus, Dominican amber
An ancient order of insects, termites are extremely common in amber. The relic genus Mastotermes (of which survives only a single large species, M. darwiniensis, in northern Australia) possesses many ancestral characteristics, including phylogenetic, morphological and behavioral similarities with cockroaches. It has also been recently established that the extinct M. electrodominicus harbored the same kinds of hindgut microbes that aid in cellulose digestion as do many extant termites: link


Juvenile praying mantis in Dominican amber (extremely rare) Unidentified microlepidopteran in Baltic amber A juvenile praying mantis in Dominican amber (RARE), and an unidentified Microlepidopteran (tiny moth) in Baltic amber.







Blue amber, Dominican Republic (extremely rare) "Blue amber" (RARE)
This beautiful and distinctive form of Dominican amber is very infrequently encountered. The exact physical and chemical processes that cause its formation are not fully understood. Curiously however, the vast majority of blue amber is completely devoid of insects or other organic materials; when present, they are usually severely crushed or washed out, offering possible testimony to the powerful geological forces involved in its creation. True "green amber" is rarer still.


Copal ('young amber'), Colombian Andes Copal ("young amber"), Colombian Andes
Before maturing into true amber, resin polymerizes into a subfossil substance called copal, that has distinct physical and chemical properties. Dated at a much younger age than amber - perhaps only a few hundred years old (much to the violent disagreement of amber dealers) - it can nevertheless contain spectacular sprays of insects, such as this huge specimen, which formed on the inside of a tree.




> AMMONITES and AMMOLITE
Relatives of the octopus, squid, and cuttlefish, these cephalopod mollusks thrived from the late Paleozoic Era (Devonian Period, ~ 400 mya) until the end of the Mesozoic Era (Cretaceous Period, ~ 65 mya), when they became extinct along with the dinosaurs and pterosaurs. Very similar in form to their other living cousins, the Chambered Nautilus (Nautilus pompilius and others in that genus), these soft-bodied, tentacled animals occupied the last chamber of a tight, spirally coiled shell. (Although, some forms were loosely coiled or partially coiled; still others were completely uncoiled and straight). As the animal grew, it would secrete a thin wall (septum) behind it that sealed off a new, slightly larger "living chamber" from the previous chambers; these would become filled with a gas-liquid mixture that provided buoyancy in the water column. The walls (septa) that separated these chambers met the internal shell wall in characteristic shapes, generally from simple curves (goniatitic) in early forms, to elaborate "hill-and-valley" patterns (ceratitic), to extremely complicated fractal-like curves (ammonitic) in late forms, which have been informally described as "jigsaw" or "seaweed" patterns. Often in fossil ammonites, these so-called suture lines clearly show through in areas where the outer shell material (the iridescent mother-of-pearl, or nacre, which is occasionally preserved) had flaked off sometime after the creature died, revealing deeper layers. Most ammonites were only a few inches to a foot or two in diameter, and smooth-shelled. Others - such as Douvilleiceras, Mammites, and the extremely rare "robust" form of Prionocyclus - bore prominent ribs, knobs, horns, or other adornments, as a defense against shell-crushing predators (chiefly mosasaurs, huge marine reptiles described as the "Tyrannosaurus rex of the Cretaceous seas"); still others reached truly gigantic proportions, reminiscent of monstrous creatures straight from the tales of Jules Verne. With enormous beasts like the Giant Squid (Architeuthis) known to exist in the ocean depths, is it possible that giant ammonites still lurk there too?



Hectickoceras ammonite, Russia Kosmoceras and Cadoceras ammonites, Russia

Sphenodiscus lenticularis, Fox Hills Formation, South Dakota
Late Cretaceous (~ 70 mya)
Both sides of this handsome specimen display the extraordinarily intricate suture patterns that are characteristic of this species. Also evident is part of the beautifully iridescent nacreous layer. A laterally flattened ammonite, this animal is thought to have been a relatively fast swimmer.





Pleuroceras pyritized ammonite chambered ammonite, Morocco

Toxoceratoides Hyphantoceras Aegocrioceras Toxoceratoides taylori, Queensland, Australia, Mid Cretaceous (~ 115 mya)
Hyphantoceras reussianum, Halle, Germany, Late Cretaceous (~ 75 mya)
Aegocrioceras spathi, Resse Hannover, Germany, Late Cretaceous (~ 130 mya)



Some unusual species of ammonite were heteromorphic, with bizarre coiling, sometimes in two, or even all three planes of rotation. Possibly, this served the animal as a mobile burrow into which it could retreat, making it difficult for a hungry predator to extract. Heteromorphs are rare, and extremely prized by collectors. ($$$)
 




Baculites compressus, Jeletzkytes nodosus, Jeletzkytes brevis
Pierre Shale Formation, Meade County, South Dakota
Late Cretaceous (~ 80 mya)
This impressive specimen was acquired in a trade with the Black Hills Institute of Geological Research. The Baculites, an example of a straight-shelled cephalopod, is over a foot long, and clearly displays the characteristic suture pattern. The two coiled Jeletzkytes ammonites came to rest lying next to each other. (J. brevis is on top of J. nodosus.)


In the late Cretaceous, much of North America was submerged under the warm shallow Western Interior Seaway, which teemed with life. One region in particular - the Bearpaw Formation of southern Alberta, Canada - has revealed two species of Placenticeras ammonite, whose organic shell mineral aragonite had not been converted to stable calcite (both forms of calcium carbonate), due to unique geological conditions. Rather, stacked layers of aragonite plates (lamellae) of varying thicknesses, together with a middle layer of randomly interspersed crystals of organic conchiolin, and several trace minerals, have the capability of refracting light into brilliant, vibrant colors. The resulting gem-like material, called ammolite, can range from bright iridescent reds (corresponding to ordered, thick lamellae) and greens (less ordered, thinner lamellae), to the very rare blues and purples (unordered, very thin lamellae), as shown in these two large specimens. Some pieces are even known as "color changers," depending on their lamellar arrangement and the angle viewed. Often rivaling precious opal in its fire and color play, ammolite was officially recognized as a gemstone by the Gemological Institute of America in 1981.
See gem pics!
See more rough ammolite: #1
See more rough ammolite: #2
See my best rough ammolite!



> EURYPTERIDS ____("you-RIP-ter-ids")
"Sea Scorpions" (Eurypterus remipes)
Fiddlers Green Formation, Herkimer County, New York (**State Fossil**)
Late Silurian dolomite (~ 430 mya)
These extinct aquatic arthropods were relatives of horseshoe crabs (Limulus), bearing a single pair of anterior feeding legs (chelicerae), four pairs of walking legs, a pair of swimming paddles, twelve flexible body segments, and a posterior tail spine (telson). This particular species typically grew to a length of under one foot. However, members of another genus, Pterygotus, could reach a maximum size of 5 feet or even larger. Equipped with large compound eyes, a broadly flattened rudder-like telson, and oversized chelicerae that ended in large claw-like pincers, they must have been extremely formidable predators. Usually, only disarticulated partial molts are fossilized; complete preservation, as in these specimens, is rare.
          Dorsal                     Ventral
Eurypterid ('sea scorpion'), Eurypterus remipes, in Silurian dolomite, NY



> TRILOBITES ____(correctly pronounced "TRY-lo-bites")

Acadoparadoxides Drotops Olenellus (ventral) Spiny Phacops (enrolled)



> LAGERSTÄTTEN




> OPALIZED FOSSILS

Opalized cockle shell








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