File:Emery (Naxos Emery Deposits, metamorphism in the Eocene & Miocene, 40-50 Ma & 16-20; Naxos Island, Aegean Sea) 6.jpg
Original file (3,039 × 1,578 pixels, file size: 4.18 MB, MIME type: image/jpeg)
Captions
Summary
[edit]DescriptionEmery (Naxos Emery Deposits, metamorphism in the Eocene & Miocene, 40-50 Ma & 16-20; Naxos Island, Aegean Sea) 6.jpg |
English: Emery from the Tertiary of Naxos Island, Greece. (~4.4 centimeters across along the base)
Emery is a rare metamorphic rock. Also known as corundite, the rock is dominated by the mineral corundum, a very hard aluminum oxide, Al2O3. Corundum is the definition of hardness 9 on the Mohs Hardness Scale. This material comes from the Naxos Emery Deposits on the island of Naxos in the Aegean Sea. Naxos is dominated by metamorphic rocks and some igneous rocks. Much of the island consists of marbles (originally limestones). Some of the original limestones had lenses of bauxite, a rock having aluminum hydroxy-oxide minerals. Upon metamorphism, the limestones were converted to marbles and the bauxites were converted to diasporites (= diaspore (AlO·OH)-dominated rocks). With further metamorphism, the diasporites were converted to corundites plus water. High fluid pressures fractured the rocks, and the fractures got filled up with corundite. Metamorphism on Naxos occurred during the Cenozoic in two main phases. A high-grade metamorphic event occurred during the Eocene, at about 40-50 million years ago. A second, intermediate-grade metamorphic event occurred during the Early Miocene, at 16-20 million years ago. The "quality" of emery in the Naxos Emery Deposits varies from relatively pure corundite, which can be blue (= sapphire rock) to corundite significantly mixed with other minerals. This emery specimen is magnetitic corundite - a magnet sticks to it. The brownish coloration facing the viewer is iron oxide staining along a fracture surface. Info. synthesized from: Urai & Feenstra (2001) - Weakening associated with the diaspore-corundum dehydration reaction in metabauxites: an example from Naxos (Greece). Journal of Structural Geology 23: 941-950. Feenstra & Wunder (2002) - Dehydration of diasporite to corundite in nature and experiment. Geology 30(2): 119-122. |
Date | |
Source | https://www.flickr.com/photos/47445767@N05/51098986271/ |
Author | James St. John |
Licensing
[edit]- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
This image was originally posted to Flickr by James St. John at https://flickr.com/photos/47445767@N05/51098986271. It was reviewed on 7 April 2021 by FlickreviewR 2 and was confirmed to be licensed under the terms of the cc-by-2.0. |
7 April 2021
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 20:10, 7 April 2021 | 3,039 × 1,578 (4.18 MB) | Ser Amantio di Nicolao (talk | contribs) | Uploaded a work by James St. John from https://www.flickr.com/photos/47445767@N05/51098986271/ with UploadWizard |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.
File usage on other wikis
The following other wikis use this file:
- Usage on en.wiktionary.org
Metadata
This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong.
Camera manufacturer | Canon |
---|---|
Camera model | Canon PowerShot D10 |
Exposure time | 1/60 sec (0.016666666666667) |
F-number | f/11 |
ISO speed rating | 80 |
Date and time of data generation | 12:31, 2 April 2021 |
Lens focal length | 11.614 mm |
Width | 4,000 px |
Height | 3,000 px |
Bits per component |
|
Pixel composition | RGB |
Orientation | Normal |
Number of components | 3 |
Horizontal resolution | 180 dpi |
Vertical resolution | 180 dpi |
Software used | Adobe Photoshop Elements 18.0 (Macintosh) |
File change date and time | 23:01, 5 April 2021 |
Y and C positioning | Co-sited |
Exif version | 2.21 |
Date and time of digitizing | 12:31, 2 April 2021 |
Meaning of each component |
|
Image compression mode | 3 |
APEX shutter speed | 5.90625 |
APEX aperture | 6.90625 |
APEX exposure bias | −0.66666666666667 |
Maximum land aperture | 4 APEX (f/4) |
Metering mode | Pattern |
Flash | Flash fired, compulsory flash firing, red-eye reduction mode |
Supported Flashpix version | 1 |
Color space | sRGB |
Focal plane X resolution | 16,460.905349794 |
Focal plane Y resolution | 16,483.516483516 |
Focal plane resolution unit | inches |
Sensing method | One-chip color area sensor |
File source | Digital still camera |
Custom image processing | Normal process |
Exposure mode | Manual exposure |
White balance | Auto white balance |
Digital zoom ratio | 1 |
Scene capture type | Standard |
Lens used | 6.2-18.6 mm |
Date metadata was last modified | 19:01, 5 April 2021 |
Unique ID of original document | 4197797CB9A1697CCFA6A93BEBA77B46 |