GLASS SAND
295. Sands suitable for making ordinary bottle glass are of widespread occurrence and therefore they have not been dealt with. High-grade sand suitable for the better quality colourless glass ware was mostly imported before the War, chiefly from N.W. Europe. During the War, however, a satisfactory alternative source discovered by the Geological Survey was developed at Loch Aline, Morvern. No estimate has been made of the resources of sand, but they are believed to be ample. As first quality Loch Aline sand is at least equal to the best continental sands* it is desirable that efforts which are being made to retain home markets should be encouraged.
HAEMATITE IRON ORE
296. Several occurrences in different parts of Scotland including the Orkney and Shetland Islands are known, most of those showing any promise having been thoroughly tested already. With the possible exception of the Sandlodge Mine in Shetland, there is none that would seen to justify further investigation. No estimates are available of any ore reserves.
LEAD AND ZINC ORES
297. Ores of these metals have usually been found together and have been worked at some time or another on quite an extensive scale in the following districts:-Leadhills and Wanlockhead, Newton Stewart, Cars- phairn, Strontian, Tyndrum, Islay and at some other localities. In recent years records of production may be summarised thus:
TABLE XXII
PRODUCTION OF LEAD AND ZINC CONCENTRATES
Year
(tons)
Zinc Concen- trates (45 per cent. Zn)
Lead Concentrates (80 per cent. Pb).
Wanlockhead
Leadhills
Tyndrum
Wanlockhead
1921
1,171
150
11
65
1922
...
2,902
1,403
58
115
1923
...
...
2,418
1,445
99
104
1924
2,322
1,420
81
4
1925
...
2,426
948
90
|
1926
...
•
3,085
1,239
1927
...
...
2,822
1,530
194
1928
...
2,709
1,421
1929
...
...
3,599
231
1930
...
...
..
4,155
153
1931
...
...
2,857
122
278
634
819
409
1932
72
...
...
...
1933
7
1934
1,898
260
1935
...
•
1936
...
...
14t
1937
20+
...
...
1938
104†
1939 1940
...
173†
54†
* See Board of Trade Working Party Report "Hand-blowndomestig
ware, 1947." From treatment of dumps.
62
3
1
Leadhills and Wanlockhead
298. These 86 mmefreabout 2 miles apart, but worged the fan2series of veins. Leadhills has been closed for nearly 20 years and Wanlockhead for 15 years. In any future consideration of the re-development of lead min- ing, however, this area is the most important. In 1947 there still remained a nucleus of miners in the district and there was the chance that other men living in the district but now employed on other work might be encouraged to return to mining if the prospect of long-term operations arose..
299. Ore reserves at Wanlockhead are known to amount to the equivalent of about 18,750 tons of 80 per cent. lead concentrates and about 12,500 tons of 45 per cent. zinc concentrates, about one half of each being reason- ably certain and the remainder "probable". There is a lack of evidence concerning any reserves at Leadhills.
300. The reserves at Wanlockhead offer a reasonable short-term mining risk, but the re-opening of the mine from the long-term point of view would have to be dependent upon the outcome of a large-scale exploratory campaign to prove and block out new ore-bearing ground. There is little direct information about the chances of new discoveries of ore of economic value being made, although it is reasonable to suppose that at Wanlockhead in particular many of the lodes would continue to be productive if explored at lower levels. The area of ground lying to the west of Leadhills and north of Wanlockhead is also promising as it may contain productive exten- sions of known veins.
:
301. The broad conclusion of the Sub-Committee is that a determined exploratory campaign based initially on Wanlockhead, and extending gradually so as to open up the area of ground between the two mines at lower levels would have a reasonable chance of proving the existence of substantial new lead-zinc resources. It is not possible on the evidence available to be more specific.
Other Areas
:
302. From the point of view of past production, four areas only have been important; these are Tyndrum, the Island of Islay and Strontian (Argyll- shire), Newton Stewart and Carsphairn (Dumfriesshire). Mining operations ceased at Tyndrum and in Dumfriesshire about 20 years ago, but nothing has been produced on the other areas since the last century. Generally speaking, present information does not indicate that ore reserves of any value exist in the mines, and geological information does not hold out any great promise that further exploration would yield substantial reserves. Nevertheless there is a prospect, for instance, at Strontian, that further exploration would prove worth while providing the undertaking was regarded as speculative, and it was understood that conclusive results one way or another could only be obtained after substantial expenditure.
303. Information is too meagre for an opinion to be given about future prospects in many of the smaller occurrences of lead and zinc ores known to our Scottish Sub-Committee and which have been tested from time to time. In one or two cases only does it suggest that further exploration might be justified.
MAGNETITE IRON ORE