Characterization of Natural Precious Opal Using Modern Spectroscopic Techniques in Ethiopia: The Case from Delanta, South Wollo

Table 2

Concentration (in ppm) for trace elements within each opal sample by ICP-OES (Ds-1: Workwasha, Ds-2: Alehuat, Ds-3: Nech-gedel, Ds-4: Abobetach, Ds-5: Chegen, and Ds-5: Gelbate).

	Ds-1	Ds-2	Ds-3	Ds-4	Ds-5	Ds-6
Ca	2,258.46	4,338.71	1,756.16	4,737.35	2,402.43	2,782.30
Al	2,634	3,152	4,287.51	2,934	4,319	1,990.78
Mg	<0.002	172.38	<0.002	47.04	81.92	<0.002
Na	3,723.24	1,130.13	1,995.66	2,019.39	595.18	3,376.62
K	2,466.55	3,416.98	1,670.00	3,894.75	1,840.77	2,461.04
P	478.91	364.58	415.69	438.16	353.58	251.51
Fe	70.31	254.39	185.95	226.41	183.93	86.50
Mn	4.91	1,157.83	7.11	7.65	2.99	4.90
Cu	0.95	0.65	0.41	0.32	0.04	0.19
Zn	1.82	1.58	1.88	1.87	1.29	0.44