USGS Bulletin 1823

METHODS FOR SAMPLING AND INORGANIC ANALYSIS OF COAL
U.S. Geological Survey Bulletin 1823

[Concentration units are %(cg/g) for the first group of elements, including Si through Mn, and ppm (m g/g) for the group of elements that includes As through Zr.]

	1633						1633A
ELEMENT	NBS VALUE^a			USGS AVERAGE^b			NBS VALUE^a			USGS AVERAGE^c
Si(%)				27	±	3.3	22.8	±	0.8*	26	±	2.6
Al				17	±	2.8	14			18	±	3.1
Fe				8.0	±	0.93	9.40	±	0.10*	11	±	1.7
Mg				2.2	±	0.32	0.455	±	0.010*	0.71	±	0.14
Ca				5.4	±	1.2	1.11	±	0.01*	1.3	±	0.31
Na				0.25	±	0.03	0.17	±	0.01*	0.16	±	0.03
K	1.72			1.3	±	0.15	1.88	±	0.06*	1.5	±	0.19
Ti				0.80	±	0.15	0.8			0.85	±	0.18
Mn	0.0493	±	0.0007*	0.076	±	0.011	0.0190			0.026	±	0.0777
As(ppm)	61	±	6*	<100^d			145	±	15*	190	±	49
B	430			440	±	46				32	±	4.0
Ba				1600	±	490	1500			910	±	160
Be	12			15	±	1.5	12			14	±	1.9
Ce				170	±	29	180			160	±	53
Co	38			38	±	4.9	46			38	±	6.2
Cr	131	±	2*	120	±	23	196	±	6*	180	±	33
Cu	128	±	5*	100	±	25	118	±	3*	93	±	21
Eu				3.1	±	0.5	4			3.4	±	0.6
Ga	49			39	±	5.8	58			54	±	11
La				96	±	13
Mo				--		--	29			28	±	6.2
Nd				60	±	15				100	±	29
Ni	98	±	3*	110	±	15	127	±	4*	140	±	19
Pb	70	±	4*	74	±	9.0	72.4	±	0.4*	76	±	12
Sc				25	±	4.0	40			29	±	5.7
Sr	1380			1700	±	230	830	±	30*	900	±	140
V	214	±	8*	200	±	24	300			240	±	36
Y				53	±	7.8
Yb				6.6	±	0.9
Zn	210	±	20*	260	±	21	220	±	10	270	±	41
Zr				180	±	29
^a certified values indicated with *; others not certified ^b average of 35 determinations 2/83 to 7/83 ^c average of 31 determinations 6/83 to 3/84 ^d lower limit of determination