Most geological collections we hear about in the news are the prettiest, oldest, youngest, largest, smallest, rarest, most expensive or have some exciting story related to them that ties them to the evolution of our planet. Dinosaurs, human remains and meteorites are particularly popular. Over the last year we’ve embarked on a major curatorial project rehousing something that is the opposite – an unglamorous collection of bags of crushed rock.
I’ll be explaining why the samples needed to be re-housed and most importantly why they are strategically important to the work of the Museum and needed to be kept for future reference. And also why we are all dressed up in protective equipment and why I had to learn to drive a fork lift truck!
The collection
The collection was made over the last decade by staff from the Centre for Russian and Central EurAsian Mineral Studies (CERCAMS), a centre based at the Museum for research on the geodynamics and metallogenesis of the former Soviet Union and its neighbouring territories, including China and Mongolia.
Mountain-building processes during the Palaeozoic shaped the Central Asian orogenic belt, forming the Tien Shan mountain range. The westernmost part of Tien Shan in Uzbekistan is known for its world-class ore deposits making this region one of the richest gold provinces of Eurasia.
Strategic importance to the Museum
By studying the isotopic signature of granite like rocks (granitoids) in the Tien Shan range and dating the absolute age of grains of the mineral zircon, the CERCAMS team has been able to gain a better understanding of the geological evolution of this region.
Rocks bearing the minerals biotite or amphibole behave like a sponge as these minerals contain crystal water that, if released, is capable of transporting and enriching metals. When metals get accumulated during processes in the crust, ore deposits may form. This has significant implications for understanding of the genesis of ore deposits. Potentially this can lead to the discovery of new ore deposits below the sedimentary cover.
One of the three big narratives in the Museum’s strategy to 2020 is sustainable futures:
“Working with other organisations, we study the effects of biodiversity loss, pollution, mineral extraction and spread of diseases and provide the expert knowledge on which to build the solutions to these issues.”
Why did we need to keep all the samples?
To study the whole rock geochemistry of each sample around 5kg is needed to be crushed to a fine dust in order to get a homogeneous and representative portion for analysis. We debated cutting down the size of the samples for easier storage but this would introduce a bias as larger fragments would be preferentially kept if we tipped crushed fragments from the tops of the bags.
The samples also support the conclusions of the research that has been carried out at the Museum. Should anyone wish to repeat any of the analyses in future years, access to the collection will be freely available. The cost of collecting, crushing, transporting and analysing the material was significant so having to make this collection again would not be a viable exercise.
Why did the samples need moving?
Many of the samples had been held temporarily in parts of the Museum that were not specifically designed for long term storage. We have future projects planned and need to use the space at South Kensington more efficiently. Therefore, we decided to move all 1,200 samples weighing around 5kg each to a location where they could be better stored.
Why did the samples need rebagging?
Many of the samples were in cloth bags or one’s hand-made from other textiles. The boxes also contained materials that are not conservation grade. Some of the bags had shown evidence of rodent activity and we found one dead moth amongst the bags.
Cotton and other shreddable textiles make excellent bedding material for rodent nests or food for hungry larvae of moths or other Museum threatening insects. As a result we took the decision to replace all bags with conservation grade Tyvek bags.
Why did we need protective equipment?
The job of rebagging created a large amount of dust so we needed masks and protective clothing. Handling bags that had shown evidence of rodent activity was also a risk. To avoid contaminating our new location we froze all samples in the quarantine facility on arrival so that any insects present would be killed.
Why did I need to learn to drive a forklift truck?
If you have read my blog previously you might be wondering why I was leading a team carrying out a large scale rock sample move? Since 2015 I have been managing three curators in the Economic and Environmental Earth Sciences Division who are responsible for the rock, ores and micropalaeontology collections. We decided that this was a priority project so as part of my new duties I received training on how to drive a fork lift truck.
The Future
The first results from the work in the Tienshan (transect 6 in Uzbekistan) have just been published by the team in the journal Gondwana Research. Results from other transects representing more of the material we house at our new location, will be published in future.
The collection we highlight here is unglamorous but underpins some strategically important research into the sustainable exploitation of minerals that is going on in the museum. Not all parts of the ores and petrology collections are unglamorous and I will be encouraging staff to write blog posts on their areas of the collection.
In the meantime, if you want to find out more about the rock collection at the Museum then you can find details of the ores and petrology collections on the website. This calendar for ores gives some examples of spectacular specimens and highlights research projects at the Museum that relate to them.