Sunday, 31 May 2015

Second Time Capsule Contents - May 17, 2015

May 17, 2015

The Kings County Museum in Kentville, Nova Scotia received two time capsules during the demolition of the Kings County Academy.  In June of 2014 we opened one of the time capsules dated from 1928 that was part of the school's original foundation.  I documented the results in detail in previous posts:

Time Capsule Opened - June 19, 2014

Time Capsule Contents - July 2, 2014

Time Capsule Contents (Continued) - July 19, 2014

Time Capsule Contents (Continued) - December 9, 2014

The other time capsule dating from the addition to the academy in 1933 had been turned into the museum at an earlier date and when opened was a mass of brown, soggy paper.  It was closed up and stored away at the museum for future work.  Both capsules containers are very similar in design and appearance with iron content as evidenced by a strong reaction to a magnet and evidence of both red and green corrosion products on the surface.  I recently started work on this second capsule which had much more green corrosion implying the likelihood of copper contents.  I have included a photograph here to show you what we were first presented with.  The bottom of the capsule and the soggy brown mass inside had considerable patches of vibrant green corrosion products.
Time Capsule 2 - Three Coins
Time Capsule 2 - First View


When turned over it came as quite a surprise to find three coins embedded in the brown mass as shown in the second photograph.  It is likely that the  green corrosion can be attributed to the several copper 1 cent coins found inside being exposed to water over a lengthy period of time.  But this was not all, over the course of the next few hours of unravelling the brown mass of soggy newspapers, I came across a total of nine coins dating from 1907 to 1933.  There were seven coins with copper content, a sliver 10 cent coin, and a nickel 5 cent coin.  Here is a list of what was found with the dates determined after cleaning:

  • 1907 1 Cent large, Newfoundland, medium corrosion
  • 1913 1 Cent large, Canada, medium corrosion
  • 1907 10 Cent, Canada, light black tarnish removed on about 95%
  • 1924 5 Cent, Canada, light corrosion
  • 1933 1 Cent small, Canada, light corrosion
  • 1933 1 Cent small, Canada, light corrosion
  • 1930 1 Cent small, Canada, light corrosion
  • Unknown 1 Cent small, Canada, heavy corrosion, size and edge same as other 1 cent Canada
  • Unknown 1 Cent small, US, heavy corrosion, phrase "WE TRUST" visible, possibly US 1 Cent, different size and edge as 1 cent Canada

All the coins were cleaned in the following steps.  Keep in mind that the goal was to reveal the date or any other identifying marks:

  1. use a soft bristled toothbrush to remove any loose material such as paper and corrosion products.
  2. use a sharpened wooden skewer to carefully pry loose any material more firmly stuck on the surface.
  3. use calcium carbonate paste made with distilled water (a mild abrasive) to remove any additional material.  This easily removed the black tarnish on the silver 10 cent coin.
  4. use distilled water to remove any left over paste rubbing with a soft cotton cloth.
  5. if necessary, use a glass fibre brush gently to expose enough of the date to make it readable.  NOTE: this is much more abrasive and is only done with the risks inherent (such as minor scratching) clearly understood by owner.
Below is an example of the effect of cleaning on one of the coins which clearly shows the value in doing at least some limited form of mechanical cleaning.  There are other cleaning methods that can be used such as chemical baths but those are outside the budget of a community museum due to the cost required for both the chemicals and the laboratory environment required for safety reasons when following this process.  These are before and after photographs of a 1913 1 Cent large Canada coin.

1913 1 Cent Reverse - After
1913 1 Cent Reverse - Before

The gentle mechanical cleaning  was able to reveal some of the scroll design around the outside edges and the date 1913.  As with using glass fibres for more aggressive cleaning you can see that some of the bright, shiny coppery patina is revealed (centre left).