For abundance data, it is normal for the values to cover many order of magnitude. For this reason it is common to quote and display the data in logarithm form as well. Values vary slightly with location.
Units are parts per billion by weight.
Units ppb by weight Notes Data given in different sources vary somewhat, reflecting the difficulty in assessing these numbers. Values given here are estimates of the average composition of stream water and are derived by a consensus and averaging process for data abstracted from references 1-2. Values for the more rare elements are probably accurate to within an order of magnitude. Values in any particular location may be very different from those given here. The units used in WebElements for all abundance data are ppb by weight which means parts per billion by weight , that is mg tonne -3 or mg per 1000 kg.