This Gemstone Switches Colours in an Instant

Hackmanite  from the Koksha Valley, Afghanistan

                                              Photochromism is a process that can be described as a change of color upon exposure to light.  A mineral that possesses this property is said to be photochromic,Technically, photochromism is defined as "the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation, where the two forms have different absorption spectra." But the term has been loosely adopted in mineralogical circles to mean the reversible change of color of a mineral upon exposure to a particular type of light.

Source:https://www.geologyin.com/2018/01/this-gemstone-switches-colours-in.html?fbclid=IwAR25jtrYM_kKiG9CTT1ERL9G1Nn0hT6tsEmV5xlD6-gicRfdukVYPWa8tUk

 The state owned Cochin Shipyard(CSL),Kerala already started the construction of two autonomous ferries(60m) for Norway's "ASKO Maritime AS". These vessels are designed by Norway's famous "Kongsberg Maritime systems" and detailed engineering design carried out by CSL. Probably these two will be the first Fully autonomous, electric ships from any of the Indian shipyards.

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Source: LIGO India

 

Lingyun-10.

           New Chinese variable thrust liquid rocket engine