| Sold | Grade | Monthly Average |
| Sep 2013 | 6.0 | $10.90 |
| Jan 2010 | 6.0 | $8.98 |
| Apr 2010 | 5.5 | $8.10 |
| Aug 2012 | 5.0 | $8.95 |
| Aug 2010 | 5.0 | $7.20 |
| Feb 2018 | 4.5 | $7.20 |
| Jun 2017 | 3.5 | $4.80 |
| Jan 2017 | 3.5 | $4.80 |
| Apr 2015 | 3.0 | $5.10 |
| May 2021 | 2.5 | $4.70 |
| Jan 2014 | 2.5 | $4.30 |
| Jan 2021 | 2.0 | $3.90 |
| Aug 2018 | 2.0 | $3.20 |
| Aug 2016 | 1.8 | $3.10 |