Tuesday 21 April 2015

Kawau Island copper mines

Visited Kawau Island off the east coast of New Zealand in the Hauraki gulf last weekend. In 1844 copper was discovered on the Island and a mine was set up next to the coast. The chimney you see below is the engine house that housed a big steam engine to pump water out of the mine.

https://farm1.staticflickr.com/7/7495253_6ee384681d_o.jpg
Here is the description of the history of the site.

http://www.svfullmonty.com/?p=8550
I loved to see the amazing copper carbonate deposits around the copper mine and on the rocks around the area.

The rocks around the site were clearly a greenish-blue copper carbonate colour.



 However the rocks around the cave entrance were more of blue colour.

This indicates the fresh water around the cave, probably flows over the rocks when it rains, is hydrating the copper and giving rise to the classic Cu2+ colour.

The basic copper carbonate is green-blue colour and is called Malachite (Cu2CO3(OH)2).
http://upload.wikimedia.org/wikipedia/commons/b/ba/Malachite-153552.jpg
 The hydrated copper carbonate is a blue colour and is called Azurite (Cu3(CO3)2(OH)2).
http://upload.wikimedia.org/wikipedia/commons/f/fa/Azuritepigment.jpg
Azurite is broken down into Malachite over time. Here is an excellent picture of a rock caught during the transition.

https://www.facebook.com/TheEarthStory/photos/a.352867368107647.80532.352857924775258/783031718424541/?type=1
Sarah Thompson in the Photon Factory works on pigments and their photo degradation. So I was interested to see if this breakdown is important for Azurite pigments.
Raphael, Madonna and Child Enthroned with Saints, The Metropolitan Museum of Art
Sure enough in Raphael's Madonna and Child Enthroned with Saints the Virgin's mantle is darkened and a green colour due to Malachite where orginally it would have been a dark blue Azurite.

A painting with it particulary well preserved is Hans Holbein's Lady with a Squirrel and a Starling.

Hans Holbein the Younger, Lady with a Squirrel and a Starling, National Gallery, London
 It was a great day and the views from the boat were well worth the trip.



Thursday 9 April 2015

Projects.org.nz

projects.org.nz

Keen to do a science and technology fair project but don't know where to start. Check out a website a group of students and teachers (including I) put together in 2012 to give students resources to do science and technology fair projects and teachers the resources to integrate science and technology fair projects with NCEA. I have just added a Facebook page and added in a new forum to the wiki. Also if you a teacher or student and want to contribute that would be great.


There are five main sections of the website including

Steps - What are the steps to complete a science or technology project? What are some tips and tricks to making award winning projects.
Pathways - A teachers resource for NCEA integration with science and technology projects.
Forum - Need help with your science and technology fair project or need help with ideas check out the forum.
Other projects - Get inspired with other students projects and where they have taken them.
Mentoring - Want to get connected with groups and researchers that can help you with your topic. Fill in the form and we can get back to you with people that can help.

Monday 6 April 2015

Lunar Eclipse

This Saturday stayed up with some leaders from Easter camp out at Bucklands beach to watch the lunar eclipse. Thanks to Jack Fowler we captured the whole event on his iphone pushed up against the eyepiece of my small 76 mm Newtonian telescope with a moon filter. Here are the shots.


Thanks also to the group that stayed up till 1pm with me to capture the eclipse that started at around 11pm.