Ancient frankincense excavated from Chinese temple

An ancient resinous incense excavated from the ruins of the Bao’en Temple in Ninjang, China, is shown to be frankincense by a combination of IR and Raman techniques. An underground palace was discovered in 2008 when an archaeological team accidentally came across it in the ruins of the temple, to reveal the largest gilt Asoka tower in the world. Among the artifacts uncovered were glass bottles, bronze mirrors, coins, silk brocade and a number of incenses derived from woods and barks, or resins and gums.

The resinous incenses were selected for study by a team headed by Lei Zhou from Lanzhou University and Qinglin Ma from the Chinese Academy of Cultural Heritage in Beijing who used near-IR and mid-IR spectroscopy and Fourier transform Raman spectroscopy to characterise them and compare them with samples of modern frankincense. Their results are described in the Journal of Raman Spectroscopy. Despite a fair degree of degradation over the last 1000 years, the old samples were identified as frankincense due to the presence of characteristic triterpenoids.

The researchers say that the multi-platform approach allows for cross-validation. When combined with the advantages of minimal sample preparation and the non-destructive or marginally destructive nature of the techniques, it makes for a powerful way to identify ancient frankincense samples.