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This web site is about a unique group of microscopically-sized fossil algae known as calcareous nannofossils or coccoliths. A brief description of coccoliths can be found here. In the Gulf of Mexico, Tertiary, and Cretaceous "Rooms" are links to numerous images of nannofossils. The images found in these links offer the viewer a perspective on the often bizarre yet interesting shapes associated with this unique group of fossil algae. In each image file, the Linnean classification is cited in italic text along with the paleontologist(s) who either described or emended the fossil's name. Also shown is the location and the relative age (epoch or stage) of the formation from which these species were collected. Most of the Cretaceous forms come from sediments outcropping in either in the southeastern part of the United States (Late Cretaceous) or western Europe (Early Cretaceous). The Tertiary images were photographed from samples donated by colleagues, some of which are topotype material. The source of these Tertiary sediments are restricted to either outcropping strata from California and Alabama, or subsurface samples from core holes drilled along the eastern Florida coast. In the Gulf of Mexico Room are images of species that have been found useful for biostratigraphic correlation along the coastal regions of the southern United States.


The Calcite Palace web site was created by Ralph Salomon, one of the finest nannoplankton palaeontologists of his generation. The site was created in 1996 when the WWW was still in it infancy. It was the first major WWW site dealing with nannofossils, and won several awards for its pioneering approach to making the data of research palaeontology freely accesible. It is still an invaluable resource and the International Nannoplankton Association is proud to maintain and develop it. A tribute to Ralph is given below. His colleagues Jim Bergen, Osman Varol and Dave Watkins are actively engaged in publishing his work and his outstanding collection of nannofossil slides, samples and micrographs is available for research use at the University of Nebraska (for access information contact Dave Watkins).

This version of the Calcite Palace has been updated and edited somewhat (by JRY) .


Calcareous nannoplankton are a very small form of algae belonging to the Phylum Haptophyta. They make up a significant portion of the microplanktic communities living in the oceans of our world and are important because of their value as primary producers in the food chain. Calcareous nannofossils are the preserved, fossilized remains of haptophytes. They too compose a significant fraction of the many sedimentary rocks that once accumulated in the ancient seas covering our planet.

The oldest known coccoliths belong to a geologic period known as the Triassic. These coccoliths lived some 200 million years ago. Thus, while great dinosaurs walked the Earth during the Late Triassic, Jurassic and Cretaceous, these small algae floated about the ancient seas. To understand the relative age of sedimentary rocks, geoscientists can use nannofossils to correlate strata of similar age or vertically stack beds of differing ages. Nannofossils are useful for these types of correlations in strata ranging in age from the Late Triassic to the Late Pleistocene. For help with geologic time, see the scale of Harland et al., 1990.


The term "nanno" is derived from the Greek word nanos meaning dwarf. Because nannofossils are so small (1/2 to 20 microns), a very powerful microscope is required to view them. The electron microscope allows the viewer to see the individual elements contributing to the structure of these small fossils and how they are actually constructed. A light microscope allows the viewer to identify nannofossils by their unique optical properties. The specimens you will see in the links described as the Tertiary, Cretaceous, and Gulf of Mexico Rooms, were originally photographed with a light microscope at magnifications slightly over 1000 times. These light or petrographic microscopes are equipped with special filters which produce polarized light and make nannofossils bright to our eyes. This brightness or birefringence and the resulting interference pattern is unique to each nannofossil species.


When you view nannofossils in a microscope, you actually see remnants of calcite secretions that were manufactured by the once living form. These secretions are similar to a skeleton that is constructed of several smaller interlocking calcite plates. Heterococcolith is a term used to describe those nannofossils in which the plates are primarily formed of a radial array of complex shaped calcite crystals. Holocococcolith is a term used to describe nannofossils constructed of small similar sized and simple shaped calcite elements. The elements composing both heterococcoliths and holococcoliths are usually smaller than 1/1000th of a millimeter (a micron), about the same size or smaller than a speck of dust.

Examples of a typical holococcolith; Syracolithus (modern) and heterococcolith Prediscophaera (Cretaceous)

When calcite or aggregates of calcite like nannofossils are rotated on microscopes equipped with polarized light, the viewer sees the illuminated calcite "wink" as the microscope stage is turned. In part, this gives each nannofossil its unique appearance and allows paleontologists to distinguish between species of the same genus. To date only a few thousand species of calcareous nannofossils have been described, but paleontologists identify new forms as different sedimentary rocks are studied.

Example of a coccolith as seen in polarized light, normal light and phase contrast (another type of special illumination used to highlight particular fetatures of coccoliths)

K/T Boundary

The viewer will perhaps note a difference in nannofossil shapes between Cretaceous and Tertiary species. About 65 to 66 million years before the present, a very significant umber of the world's species seem to have disappeared at a time that coincides with this boundary event. On land, the most "characteristic" casualties of the Cretaceous-Tertiary boundary are of course the Dinosauria, but the change is also reflected at the microscopic level in marine plants and animals. In the fossil record, the difference between Cretaceous and Tertiary nannofossil species is perhaps best noted by differences in size and diversity and may be best illustrated in forms referred to as placoliths and muroliths (elliptical disk-shaped heterococcoliths). Early Tertiary nannofossil assemblages are less diverse and individual species are generally much smaller than their Cretaceous progenitors. Additionally, geometric forms at the end of the Cretaceous are generally restricted to cubes (Micula), whereas early Tertiary geometrically-shaped nannofossils are characterized by flattened circular disks (Biantholithus), cylinders (Fasciculithus), and rosette-shaped forms (Discoaster). A few examples of nannofossil species that become extinct at the end of the Cretaceous (Maastrichtian) are shown in the Cretaceous Room whilst images of those nannofossils that arose and flourished during the Tertiary epochs referred to as the Paleocene, Eocene, and Oligocene are shown in the Tertiary Room.

Ralph Salomon

Ralph Salomon was born on September 26, 1949 in Memphis, Tennessee. He received his BS in Anthropology and Religious Studies from the University of Southern Mississippi in May 1973. Four years later, in August 1977, after having worked with Core Lab and with Michael Baker, he entered the graduate program in geology at Mississippi State University. First, he completed the requirements for an undergraduate degree in geology then finished the course requirements for the MS degree in geology in the Department of Geology and Geography. He completed his MS thesis on the nannofossils from the Campanian Tupelo Tongue and was awarded the MS degree from Mississippi State University in December 1983.

Ralph joined Amoco in the Fall of 1982 as an exploration geologist in New Orleans, but in 1988 transferred into their Gulf of Mexico Neogene biostratigraphy group, where he pursued his interests in calcareous nannofossils. His subsequent transfer to the Amoco Exploration & Production Biostratigraphy group in Houston during 1989 allowed him to continue his interests in the Gulf of Mexico Neogene. At the same time, it allowed him to pursue a number of diverse international projects in mid-Cretaceous to Cenozoic nannofossils. In the Fall of 1994, Ralph asked to be transferred back into exploration, within Amoco’s Angola exploration group, where he could provide his biostratigraphic and geological expertise in this important geological play. Diagnosed with throat cancer during August of 1998, Ralph established temporary leave from Amoco and pursued his original interests in the Campanian nannofossil biostratigraphy of Mississippi.

Ralph, an excellent geologist and an exceptional nannofossil paleontologist with a keen "eye", was one of the foot soldiers in the industrial application of nannofossils. He created the "Calcite Palace" website, which demonstrates his depth of knowledge in the field of nannofossils and his love for technology. This site has been used by numerous nannofossil workers in academia and industry as a reference, and as a basic tool for the teaching of micropaleontology. Ralph had no published articles in the field of nannofossils, partly because he was such a perfectionist, but also because of his varied interests and his dedication to exploration. Having said that, he was in the process of publishing his first paper on the Santonian-Campanian boundary in Mississippi when his untimely death occurred. For those of us who are familiar with his MS thesis from 1983, the taxonomic documentation of these incredible assemblages (32 plates, and many of these micrographs appear on his website) is still current. We hope to finalize his work on the Campanian of east central Mississippi, including his recent manuscript on the Santonian-Campanian boundary, and to publish his thesis essentially intact.

Ralph was a loving, caring father and husband and at all times a gentle man. He is survived by his wife Donna, to whom he was married for 20 years, and by his son Andrew, who is 10 years old. We offer them our heartfelt sympathies over their great loss and wish both of them a prosperous and long life.

Drs. Osman Varol, Jim Bergen, and Ernest Russell.