Éditeur(s) : Paris : Adrien Egron ; Imprimerie de Gueffier ; Baudouin frères; Imprimerie de Fain

Droits : Domaine public
Provenance : Archives départementales de Guadeloupe
Permalien : http://www.manioc.org/patrimon/HASH0162c27c3995e1f288e6dcb5
HASH0162c27c3995e1f288e6dcb5

Éditeur(s) : Fort-de-France : Imprimerie du Gouvernement
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Communauté d'agglomération de La Rochelle. Médiathèque Michel-Crépeau
Permalien : http://www.manioc.org/patrimon/MMC16033
MMC16033

Siècle(s) traité(s) : 17
Droits : Domaine public
Provenance : Archives territoriales de Guyane
Permalien : http://www.manioc.org/patrimon/GAD11008
GAD11008

Éditeur(s) : Paris : Baudouin Frères
Siècle(s) traité(s) : 17
Droits : Domaine public
Provenance : Communauté d'agglomération de La Rochelle. Médiathèque Michel-Crépeau
Permalien : http://www.manioc.org/patrimon/MMC16129-2
MMC16129-2

Éditeur(s) : HAL CCSD GIA - Gemological Institute of America
Résumé : A new opal deposit was discovered in 2008 near the village of Wegel Tena, in volcanic rocks of Ethiopia's Wollo Province. Unlike previous Ethiopian opals, the new material is mostly white, with some brown opal, fire opal, and colorless "crystal" opal. Some of it resembles Australian and Brazilian sedimentary opals, with play-of-color that is often very vivid. However, its properties are consistent with those of opal-CT and most volcanic opals. Inclusions consist of pyrite, barium-manganese oxides, and native carbon Some samples show "digit patterns", interpenetrating play-of-color and common opal, resembling fingers. The opaque-to-translucent Wegel Tena opals become transparent when soaked in water, showing a remarkable hydrophane character. White opals from this deposit contain an elevated Ba content, which has not been reported so far in opal-CT. The fire and crystal opals are prone to breakage, while the white, opaque-to-translucent opals are remarkably durable. The proportion of gem-quality material in the Wegel Tena deposit seems unusually high, and 1,500 kg have already been extracted using rudimentary mining techniques. The deposit may extend over several kilometers and could become a major source of gem-quality opal
ISSN: 0016-626X

hal-00560177
https://hal.archives-ouvertes.fr/hal-00560177

Éditeur(s) : HAL CCSD Geological Society
Résumé : Gem opals from Wegel Tena, Wollo Province, Ethiopia, occur in Oligocene rhyolitic ignimbrites. They display a unique geochemistry, with some samples yielding the highest Ba concentrations ever recorded. They are generally much richer in chemical impurities than opals from other localities. For example, the sum Al+Fe or the sum Na+Mg+Ca+K+Ba are often higher. These geochemical features make them easy to distinguish from other opals worldwide. We observed strong geochemical variations and some good positive correlations in our samples, such as Al+Fe vs. Na+Mg+Ca+K+Ba, Al vs Ca, or Ba vs Ca. This shows that the crystallography of opal has controlled, at least in part, the incorporation of chemical impurities, although opal is not well-crystallized. In addition, the multimodal distributions of several chemical impurities (e.g. U vs Sr, Al vs Ca, Ba vs Ca, etc.) suggest at least two origins of silica: weathering of feldspars and weathering of volcanic glass. In addition, opals from Wegel Tena contain numerous well-preserved microscopic plant fossils. Moreover, their host rock exhibits features typical of pedogenesis (abundant clays, desiccation cracks, and grain size sorting). We propose that the opals at Wegel Tena formed during the Oligocene period when volcanic emissions stopped for a time long enough to allow weathering of ingimbrites and therefore liberation of silica. This accompanied the formation of soil and development of plant life, and some plants were trapped in opal.
ISSN: 1467-7873

hal-00767555
https://hal.archives-ouvertes.fr/hal-00767555
DOI : 10.1144/1467-7873/10-MINDEP-058

Éditeur(s) : Cayenne : Imprimerie du gouvernement
Résumé : Année 1862
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Collectivité territoriale de Guyane. Bibliothèque Alexandre-Franconie
Permalien : http://www.manioc.org/patrimon/FRA11267
FRA11267

Éditeur(s) : Paris : Lamy
Siècle(s) traité(s) : 18
Droits : Domaine public
Provenance : Collectivité territoriale de Martinique. Bibliothèque Schoelcher
Permalien : http://www.manioc.org/patrimon/SCH13192
SCH13192

Description : Récit de voyage en Amérique avec une partie sur plateau des Guyanes et sur le Brésil. Gravures
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Philippe Batrosse - Libraire à Cayenne
Permalien : http://www.manioc.org/patrimon/HASH017ff277fc4ae32658ca07cf
HASH017ff277fc4ae32658ca07cf

Éditeur(s) : Paris : Librairie Académique D. Perrin
Description : Simón José Antonio de la Santísima Trinidad Bolívar de la Concepción y Ponte Palacios y Blanco, communément appelé Simón Bolivar et surnommé le Libertador, est une figure emblématique de l'émancipation politique des colonies espagnoles d'Amérique du Sud.
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Ville de Pointe-à-Pitre. Réseau des bibliothèques
Permalien : http://www.manioc.org/patrimon/PAP11101
PAP11101

Éditeur(s) : [S.l.] : Imprimerie du Gouvernement
Description : Organisation administrative de différents secteurs publics de la Martinique en 1893 précédée d'une description géographique et historique de l'île.
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Ville de Pointe-à-Pitre. Réseau des bibliothèques
Permalien : http://www.manioc.org/patrimon/HASH2d1c310a7e79daee9f5de1
HASH2d1c310a7e79daee9f5de1

Éditeur(s) : [S.l.] : Berger-Levrault
Siècle(s) traité(s) : 20
Droits : Domaine public
Provenance : Université des Antilles. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/HASH01914504e0d9a3778d6bd871
HASH01914504e0d9a3778d6bd871