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Showing results for tags 'tukwila formation'.
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Tiger Mountain Amber (Tukwila Fm./Renton Fm. [Boundary], Middle to Late Eocene)
Barrelcactusaddict posted a gallery image in Member Collections
From the album: Fossil Amber and Copal: Worldwide Localities
- Subjects: Three exceptional specimens of amber, recovered from exposures on Tiger Mountain, Washington State; this is the second of two videos detailing the specimens' natural fluorescent and phosphorescent responses: longwave UV light (Convoy S2 flashlight) was used in this entry. All were prepared by hand using a diamond needle file, 240 to 3,000 grit SiC sandpaper, and chromium oxide (ZAM compound) on a Selvyt microfiber cloth. - Amber's Source Formations and Age: The amber-bearing coal contained within the the Tiger Mountain, Tukwila, and Renton Formations spans a geologic timescale ranging from Middle to Late Eocene in age (~41.3-33.9 Ma). - About Amber Phosphorescence: Phosphorescence is the noticeably-extended emission of radiation from an illuminated subject, after the source of illumination has been removed; the atoms of certain hydrocarbons within the amber, when irradiated by high intensity UV wavelengths (LED or dedicated UV light sources), achieve a higher energy or "excited" state; the rotation of atoms becomes the opposite of their rotation in their grounded "non-excited" state, allowing for a longer release of radiation (light). The light emitted in fluorescence and phosphorescence is always a longer wavelength than the source of illumination. *Regrettably, my camera could not record the full duration of the phosphorescence of these specimens, or all other specimens (Chiapas, Sumatra, Baltic, Claiborne, Dominican), for that matter; multiple tests on all three Tiger Mountain specimens showed an average response of nearly 8 seconds, after 4 seconds of sustained direct illumination. These results are comparable to that of the Chiapas amber specimen from one of my previous videos. Source: https://file.dnr.wa.gov/publications/ger_ri21_strat_eocene_king_co.pdf© Kaegen Lau
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From the album: Fossil Amber and Copal: Worldwide Localities
- Subjects: Three exceptional specimens of amber, recovered from exposures on Tiger Mountain, Washington State; this is the first of two videos detailing the specimens' natural fluorescent and phosphorescent responses: 140 lumen LED light (yellow phosphor) was used in this entry. All were prepared by hand using a diamond needle file, 240 to 3,000 grit SiC sandpaper, and chromium oxide (ZAM compound) on a Selvyt microfiber cloth. - Brief Description of Deposit: Tiger Mountain amber occurs in lignitic coal seams, mainly contained within two Geologic Formations, namely the Tukwila and Renton (along their boundary); there is also a third, the aptly-named Tiger Mountain Fm., that hosts amber-bearing coal, though not to such a degree as the former two. The Tiger Mountain Fm. (roughly 2,000 ft. in depth) underlies and is inter-bedded with the younger Tukwila Fm., while the Tukwila Fm. is overlain by the Renton Fm.: the amber-bearing coal contained within the three Formations spans a geologic timescale ranging from Middle to Late Eocene in age (~41.3-33.9 Ma). - About Amber Fluorescence: The light blue fluorescence emitted by some of this amber upon exposure to LED and sunlight, bears a remarkable resemblance in color and intensity to that of blue Dominican amber. Various aromatic hydrocarbons, naturally contained within the blue variety of amber, are responsible for this fluorescence. Blue amber is commercially mined from three major sources: Sumatra (Indonesia), the Dominican Republic, and limited production from Chiapas (Mexico) deposits. Source: https://file.dnr.wa.gov/publications/ger_ri21_strat_eocene_king_co.pdf© Kaegen Lau
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Tiger Mountain Amber (Upper-Tukwila/Lower-Renton Formations [Boundary], Middle to Late Eocene)
Barrelcactusaddict posted a gallery image in Member Collections
From the album: Fossil Amber and Copal: Worldwide Localities
Amber from Tiger Mountain, Washington State, U.S.A. Same subjects in separate video depicting their fluorescence. Total weight is 0.4g, each piece measuring only a few millimeters in length. Subjects: Tiger Mountain Amber (Upper-Tukwila/Lower-Renton Formation [along boundary], Middle to Late Eocene) Lighting: Quantum 140 lumen LED light (yellow phosphor) Recording: Samsung WB35F© Kaegen Lau
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Tiger Mountain Amber (Upper-Tukwila/Lower-Renton Formations [Boundary], Middle to Late Eocene)
Barrelcactusaddict posted a gallery image in Member Collections
From the album: Fossil Amber and Copal: Worldwide Localities
Incredible blue fluorescence in amber from Tiger Mountain, Washington State, U.S.A. No longwave UV light has been used here; these select pieces fluoresce in the same LED light conditions as Dominican blue amber, and with a strikingly similar coloration. Commercial quantities of blue amber have been officially described to be found in the Dominican Republic, Indonesia, and Mexico (Chiapas); to my knowledge, blue amber has never been described, much less documented, from North American deposits. Total weight is 0.4g, each piece measuring only a few millimeters in length. In the fluorescent video & image, specimens were submerged in water in a borosilicate glass petri dish; also, an additional video and image of the subjects when dry. *Please note there are several condensed air bubbles on surfaces of amber and glass. Subjects: Tiger Mountain Amber (Upper-Tukwila/Lower-Renton Formation [along boundary], Middle to Late Eocene) Lighting: Quantum 140 lumen LED light (yellow phosphor) Recording: Samsung WB35F© Kaegen Lau
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Amber (Tukwila Fm./Renton Fm. [Boundary], Middle to Late Eocene)
Barrelcactusaddict posted a gallery image in Member Collections
From the album: Fossil Amber and Copal: Worldwide Localities
3.0g of amber from the 9.2g lot depicted in the associated entry. This amber is middle to late Eocene in age (about 41.3-33.9 Ma), and comes from coal seams along the boundary of the upper Tukwila/lower Renton Formations. It is found in association with Pinus sp. and Metasequoia occidentalis remains, which were the most probable sources of the amber; association with Metasequoia sp. is even more prevalent among the amber from the Blakeburn Mine (i.e., amber from the Allenby Fm. near Coalmont), as Metasequoia imprints are especially abundant at that site.© Kaegen Lau