The next step in the study was the selection of headstones from each cemetery to be included in the research. In this process, the team considered the following questions: 1) Will the type of marble make a difference in the removal or regrowth of
microorganisms and biological activity?
2) Will localized environmental conditions such as sun or shade, or orientation in the cemetery affect the regrowth?
3) Are there seasonal effects for cleaning? For example, is it better to clean in the spring or fall?
There are three main stone types commonly used to create federally-issued headstones. These stone types include 1) Imperial or Royal Danby, a white or bluish white marble form Danby , VT; 2) White Cherokee, a white-grayish marble from Tate, Georgia; and 3)Colorado Yule, a white-creamy marble from Marble, CO. Of the three stone types, the White Cherokee is the most easily recognizable based on its color and large grain size. The Royal Danby and the Colorado Yule are less easily distinguished. The team recommended where possible that testing be performed on two types of stone in each cemetery. One set of tests should include the White Cherokee Georgia Marble. The second set of tests should include Royal Danby or Colorado Yule marble.
Testing also included sunny and shady locations to help account for possible differences arising from local environmental variations. Thus, half of the White Cherokee Georgia Marble headstones included in the study should be located in predominantly shady locations while the other half should be located in predominantly sunny locations within each cemetery. The same criteria also applied to the second set of Royal Danby/Colorado Yule headstones.
Finally, in order to determine if seasons affected cleaning and biological regrowth, one set of headstones were cleaned in the spring and on set of headstones were cleaned in the fall.
Once the testing criteria were established, Sarah Amy Leach and Karen Ashton contacted each cemetery director and informed them about the testing program in June 2005. They created a one page briefing sheet and an informational Q&A document for the project in order to educate VA staff and visitors to the cemetery about the study. Additionally, informational signs were installed at each cemetery.
Figure 1. Example of the informational sign placed in each cemetery for the duration of the study.