Rerieics — The Mining Journal. 521 



structure cannot be relied upon when we consider opal, serpentine, 

 and wad, tlie felspars, apatite, and tourmaline, as in geometric form 

 or composition they afford no support to precise definitions. 



Tlie question of most importance at the present day is what is 

 a mineral from the commercial point of view. In regard to mineral 

 rights, " coal, ironstone, slate, or other minerals" are usually specified 

 in legal documents, and, as Professor Gregory remarks, none of these 

 are really mineral species. In official publications, in the Mining 

 Statistics formerly issued by the Geological Survey (see pt. ii for 

 1858), various clays, as well as chalk, building-stones, sand, etc., 

 were included under " Earthy Minerals " ; and in the present reports 

 issned bj- the Mining Inspectors of the Home Office practically every- 

 thing mined or quarried is included under the heading of " Mineral 

 Products ". 



The result is that every geological formation, and practically the 

 whole of the British Islands, might be considered to contain " ungotten 

 minerals " at a greater or less depth. A common-sense list of all 

 such minerals seems impossible, and therefore in the case of legal 

 documents it would seem necessary in future to specify everj' mineral 

 of which the right of working was reserved, and to omit the vague 

 reference to " other minerals ". In the new Parliamentary Budget 

 (as it stands at present) sand, gravel, chalk, and common brick-clay 

 are to be exempted from duty. As remarked by Professor H. Louis, 

 it is possible that common clay maj- some day be utilized as a source 

 of aluminium ; moreover, in some places it may be difficult to separate 

 " common brick-clay " from terra-cotta clay, or other clay that may 

 be put to special use. Seams of coal that cannot now be worked with 

 proHt may be mined in the course of time. 



Professor Gregory concludes that " A mineral of commercial value 

 may be defined as a constituent of the earth's crust which, if organic 

 in origin, has been altered by fossilization, and which has a value of 

 its own apart from its value as a soil or as a support " ; and that the 

 question " when a surface-material acquires such economic value that 

 it should be included in the category of commercial minerals must be 

 determined for each case as it arises, but should occasion no serious 

 difficulty ". 



III. — The Seventy-fifth AifNivERSAKr of the Mining Journal. 



' jlHE Mining Journal, which claims to be " the oldest Mining Paper 

 J_ and the Pioneer of the Technical and Trade Press of the World", has 

 issued a seventy -fifth Anniversary Number, August, 1909. We take 

 it that it is the oldest existing paper devoted to the subject, inasmuch 

 as it absorbed at an early date The Mining Eevietv, which had before 

 been published quarterly. The career of the present journal coincides 

 practically with the history of modern mining. The opinion is 

 expressed that " the mining output of the past ten years is equal 

 to that of the whole previous history of the world". Coal, iron, 

 copper, zinc, and gold, as well as manganese, aluminium, nickel, oil, 

 nitrates, and phosphates, are included in the estimate. 



