340 REPORTS ON THE STATE OF SCIENCE. 
about which too little is known in respect to the ore quantities to make 
it possible to give any details. Among these is Mertaimen, with an ore 
area stated to contain 10,000 m*. If we put all these ore deposits at 
20 M.T. we get a round figure for the whole ore quantity in Norrbotten 
of 500 M.T., viz. :— 
M.T. 
Kiirunnayaara . : : ; ‘ ; ; 5 . 300 
Gellivare . ; : é a ; ; ; : ALMGT 
Ekstrémsberg . ; ‘ : . : wala) 
Svappavaara ‘and Leveiiniemi ; : ; ; ; on 
Luossavaara .. - ; : : : P Spine si) 
Tuollavaara . j ; : : 8 
Mertainen and other ‘smaller deposits : , : 4920 
Total . = 300 
3. Ore Province of Northern Norway. 
Here we are on more uncertain ground than in the preceding case, 
not only because very few attempts have been made to arrive at a true 
conception of the ore quantities in separate ore districts, but also because 
the experience won in the practical mining of this kind of ores only dates 
from the last few years. Thus we know nothing about the depth to which 
the workable ores reach 
These ores occur, as stated above, in the metamorphosed Cambro- 
Silurian schists together with limestone. They show in many places an 
extension of several kilometres in length, and at the same time a con- 
siderable thickness. If one regarded these ores as ordinary stratified 
formations, only altered by regional metamorphism, one would have to 
assume an extent of several kilometres also in the direction of the dip. 
But such a conclusion might be highly misleading with regard to the 
ore supply. ‘The possibility that these ores are secondary concentrations 
in the higher zone must be kept in mind, and, consequently, it does not 
seem allowable to calculate to any great depths before we have gained a 
wider experience in this point. 
As already stated, these ores are in general very lean, and they often 
go below the limit of being workable. As they cannot be smelted directly, 
they must first be treated by magnetic concentration, and in this process 
the non-magnetic part of the iron, 2.e., hematite, iron silicates, &ec., is 
lost. From such ores, showing by analysis 40 per cent. of iron, only 20 per 
cent. or a still less percentage may be utilised. Often the ore deposits, 
though extensive in the direction of the strike, are narrow, or when 
thicker they contain barren country rock to such an extent that the cost 
of mining will be too expensive. In many cases it seems difficult to trace 
the limit between ore and iron-bearing rock, which circumstance, of 
course, makes the estimation of the ore quantity highly speculative. On 
the other hand, the concentrated ore in the form of an easily reducible 
briquette, with 65 per cent. to 68 per cent. of iron, and practically with- 
out sulphur and phosphorus, is a very valuable product which will, when 
produced on a large scale, become a factor of great importance for the iron 
industry of Western Europe. 
_ Dunderland is the greatest ore-field of this province. The ore area 
was estimated by me in the year 1894 at one million square metres in 
round numbers. In 1899 Mr. Hasselbohm calculated it still higher, viz., 
1,290,000 m. Starting from the first-mentioned size of the ore area, and 
