Where Did the Titanic Headstones Come From?

All but one of the 150 victims of the Titanic disaster lie beneath identical “black granite” headstones. The marker of Thomas F. Baxter was damaged, so HRM sought to replace it, but there was no historical record of where these headstones came from. The solution had to be found scientifically. As DNA is unique to each living thing, so every rock also has a unique set of characteristics (age, minerals, texture, and chemical composition) that sets it apart from every other rock. If true, the headstones should match only the quarry where they were extracted. But there are tens of thousands of quarries in the world, so where was the right one? This presentation will describe how the source quarry was located, using the best sleuthing techniques of Sherlock Holmes and CSI.