Southwest Florida Fossil Society

"To Inform and Educate"
is to promote and foster the science of paleontology through the collection, identification and preservation of fossil remains and providing a regional forum for education, training and experience in the scientific field.
Monthly Meeting July 14, 2018 at 7pm at 118 Sullivan St. in Downtown Punta Gorda


Our speaker will be Geraldine Vest, Ph.D., FGA, GG(GIA).

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation. The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet (UV) region of the spectrum, and thus invisible to the human eye, while the emitted light is in the visible region, which gives the fluorescent substance a distinct color that can be seen only when exposed to UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stop. Most materials need an impurity “activator” to cause fluorescence; for example, manganese impurities in many of the Franklin and Sterling Hill, New Jersey, material gives the materials the ability to fluoresce—willemite a brilliant green and calcite a brilliant red. Materials do not need to be crystalline—many plastics and glasses fluoresce.

Phosphorescence is the afterglow that occurs when the high energy source is just turned off; it may last a few seconds or a long time. Only a few fluorescent materials also show this phenomenon; they can glow the same color as the fluorescence or a totally different color. Strangely, when the blue Hope diamond, now in the Smithsonian, was bombarded with ultraviolet light did not fluoresce, but when the UV light was turned off, it immediately phosphoresced red for a short time.

The program consists of a power point presentation followed by a display of minerals and gems from the collections of: Jim Davis, Robert Campbell and Geraldine Vest, with a question and answer period.


Geraldine M. Vest received a BS degree in Metallurgical Engineering from Purdue University. After working for Chicago Bridge and Iron Company in Chicago as a Welding Engineer, she returned to Purdue University and earned a Ph. D. in Materials Engineering. She accepted the university offer and worked as a professor of Materials Engineering until she retired. Much of her research was in the area of microelectronic materials for electrical circuits.

During a sabbatical year spent in London England, she studied gemmology in the evenings at Sir John Cass Polytechnic Institute; after passing several days of tests, she became a gemmologist and was elected as a Fellow of the Gemmological Association of Great Briton (FGA), with distinction. Upon returning to the USA, she took the courses on colored-stones and diamonds with the Gemological Institute of America, earning a degree as a graduate gemologist GG(GIA).

Geraldine is an avid mineral and gemstone collector. As president of the Gulf Coast Mineral, Fossil & Gem Club of Venice, Florida she teaches courses in beginning mineralogy and gemstone identification to the club members.

FOSSIL (Fostering Opportunities for Synergistic STEM with Informal Learners) is a project funded by the National Science Foundation and headquartered at the Florida Museum of Natural History in Gainesville. FOSSIL is developing a national community that includes amateur and professional paleontologists; our research indicates that more than 60 amateur fossil clubs and societies exist in the USA, but they are not well coordinated in their activities. Overarching goals of the FOSSIL Project include enhanced collaborations between amateurs and professionals, knowledge-building about paleontology, access to resources for lifelong learning, and development of a viable learning community focused on topics such as collections (including digitization), evolution, and K-12 outreach. In addition to more traditional means, such as our newsletter (available at, FOSSIL is developing an interactive online community ( and using social media (Facebook and Twitter) to foster communication and interactions, and thus promoting the concept of 'social paleontology.' "
Watch "Good Question: Why is Venice the 'shark's tooth capital of the world?'" on YouTube
Click Fossil Club Meetings for more information.