An X-Ray Diffraction Analysis of the Patina of the Statue of Liberty

Abstract

An X-ray powder diffraction analysis has been performed on several samples from the naturally occuring patina of the Statue of Liberty. This work, which was conducted as a service to the National Park Service as part of the restoration activities for the Statue, was performed to assess the impact of acid deposition on the phase composition of the patina. Samples of the patina that were obtained from various locations on the copper skin of the Statue were found to consist primarily of the basic copper sulfate known as brochantite or CuSO4·3Cu(OH)2. Another less stable form of basic copper sulfate CuSO4·2Cu(OH)2 known as antlerite was also observed in samples taken from areas that are more exposed to the incoming weather in New York harbor. The presence of antlerite supports the contention that acid deposition is promoting undesirable changes in the phase composition of the patina. Analyses were also performed on patina samples that were taken from pieces of the Statue's copper skin that had been removed in the years 1905 and 1980. X-ray powder diffraction of the corrosion product on the 1905 sample showed that it consisted primarily of the stable brochantite phase, while the 1980 sample displayed both copper chlorides as well as the less stable antlerite. Both samples also contained cuprite (Cu2O) which appears to have formed prior to either of the sulfates.

The HighScore suite

“…As an example of this new feature, we have reinvestigated the analysis of the patina of the Statue of Liberty published in the first volume of Powder Diffraction (Matyi and Baboian, 1986). This is illustrated in Figure 4 where we present respectively the scan of Figure 4 from Matyi and Baboian (1986), the converted scan and the phase quantification by the Rietveld analysis of the sample, which was not done at that time.…”

“…This is illustrated in Figure 4 where we present respectively the scan of Figure 4 from Matyi and Baboian (1986), the converted scan and the phase quantification by the Rietveld analysis of the sample, which was not done at that time.…”

“…As an example of this new feature, we have reinvestigated the analysis of the patina of the Statue of Liberty published in the first volume of Powder Diffraction (Matyi and Baboian, 1986). This is illustrated in Figure 4 where we present respectively the scan of Figure 4 from Matyi and Baboian (1986), the converted scan and the phase quantification by the Rietveld analysis of the sample, which was not done at that time.

Figure 4. (Color online) Illustration of the bitmap-to-scan converter in HighScore 4.0: (a) scanned picture of the powder pattern taken by Matyi and Baboian (1986), (b) converted scan from the bitmap, and (c) resulting quantitative Rietveld analysis.

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Silica- and sulfate-bearing rock coatings in smelter areas: Products of chemical weathering and atmospheric pollution I. Formation and mineralogical composition

“…It is also associated with brochantite in Cu-bearing patinas on bronze statues (e.g. Statue of Liberty, Matyi and Baboian, 1986).…”

Photochemical Copper Coating on 3D Printed Thermoplastics

“…Herein, we have demonstrated that malachite, which is one of the major compositions of the surface composition of the Statue of Liberty in New York City 19 , can be transformed to copper by non-contact laser treatment. Further malachite mixed in acrylic paint can be used for coating on 3D printed objects and later transformed to copper after one-step laser treatment.…”