Toe

Spot 3

Spot 1

Spot 2

Clean Spot

Joint Base to Statue

Base

Balzac

Bronze corrosion and patina analysis

The following slides are produced utilizing excel over lays of spectra taken on the Balzac sculpture in June before the statue was re patinated. •2 sets of data were taken with a 0.001” Cu filter in the Bruker handheld xrf instrument.

•One at 40kV and 3 micro amps (the first 3 slides below). •The other set was taken at 15 kV and 15 micro amps (the last 2 slides below)

0

100

200

300

400

keV

10 15 20 25 30

balzac join green corosionbalzacbase.40.3balzacspot1.40.3balzacspot2.40.3balzacspot3.40.3balzactoe.40.3

Pb LPb L

Cu sum peaks

Sn K

Sn KRh elastic and

inelastic scatter

The Cu alloy contains a small amount Zn, Sn and a trace of Pb. See next slide for Cu and Zn

0

10000

20000

30000

40000

keV

5 6.67 8.33 10

balzac join green corosionbalzacbase.40.3balzacspot1.40.3balzacspot2.40.3balzacspot3.40.3balzactoe.40.3

Cu K

Cu K

Zn KFe K

The Cu from the bulk alloy is attenuated depending on the thickness of the corrosion. Based on this the corrosion is thickest in the joint.

0

250

500

750

1000

keV

2 3.83 5.67 7.5

balzac join green corosionbalzacbase.40.3balzacspot1.40.3balzacspot2.40.3balzacspot3.40.3balzactoe.40.3

Fe K

Fe K

Ca K

The join contained Fe and Ca build up,. Likely the product of water from sprinklers drying over the years.

0

13

25

38

50

1.5 1.93 2.35 2.78 3.2

balzac clean spot 15.15balzac join green corosion 1515balzacbase.15.15balzacspot1.15.15balzacspot2.15.15balzacspot3.15.15balzactoe.15.15Cl

S

There is a trace of Cl in the joint and a trace of S in spot 2.

0

200

400

600

800

keV1 2.63 4.25 5.88 7.5

balzac clean spot 15.15balzac join green corosion 1515balzacbase.15.15balzacspot1.15.15balzacspot2.15.15balzacspot3.15.15balzactoe.15.15

The join contained Fe and Ca build up,. Likely the product of water from sprinklers drying over the years.