Rock varnish on architectural stone: microscopy and analysis of nanoscale manganese oxide deposits on the Smithsonian Castle, Washington, DC

Heritage Science

Table 2 Portable x-ray fluorescence spectrometry net intensity results for rock varnish and fresh fractured Seneca sandstone surfaces shown in Fig. 6

Element/net intensities	X-ray line	Black₁	Black₂	Black B_avg	Red₁	Red₂	Red R_avg	B_avg/R_avg
K	K_α	3604	3089	3347	2960	3542	3251	1.03
Ca	K_α	3765	3210	3488	1883	1955	1919	1.8
Ti	K_α	10,788	9928	10,358	10,474	10,302	10,388	1.00
Mn	K_α	357,188	328,229	342,709	4992	10,533	7763	44.15
Fe	K_α	360,371	333,692	347,032	319,972	328,254	324,113	1.07
Ni	K_α	382	376	379	256	301	279	1.4
Cu	K_α	3363	3212	3288	2119	2261	2190	1.5
Zn	K_α	2676	2596	2636	1428	1614	1521	1.7
Ga	K_α	324	–	162	563	555	559	0.3
Rb	K_α	6221	5948	6085	6606	7420	7013	0.9
Sr	K_α	12,303	11,791	12,047	12,317	13,234	12,776	0.9
Y	K_α	4643	4264	4454	4442	4430	4436	1.00
Zr	K_α	44,471	39,197	41,834	41,126	39,503	40,315	1.04
Pb	L_α	7753	8219	7986	1403	1565	1484	5.4
Fe/Mn		1.009	1.017	1.013	64.10	31.16	41.8