AS 1141.26:2019 pdf free
AS 1141.26:2019 pdf free.Methods for sampling and testing aggregates
It is common practice in Australia to have petrological slides prepared in specialized commercial laboratories that operate automated equipment capable of producing slides that are of uniform thickness throughout their surface area and conform to the requirements given above.
NOTE If this service is used and if the laboratory is contracted for additional services, the laboratory should be informed of other analytical procedures that will be performed (e.g. Reflected light petrology and EDX) on the same sample in order that other thin sections or other specimens are prepared correctly.
The procedure shall be as follows:
(a) Identify the rock type by examination of the hand specimen and from sample advice provided.
NOTE If the rock type identification requires the examination of thin sections, the procedures of ASTM C295 would be preferable to this method.
(b) Examine each thin section under the microscope and identify which minerals present are primary and which are secondary. Also identify the presence of veinlets or microcracks in the fabric of the rock and the presence of secondary minerals as linings or infillings within vesicles or primary pores.Record the major compositional and textural features of the section and the distribution of secondary minerals within the fabric of the rock.
(c) Set-up the mechanical stage unit at the starting point of the first traverse line. Determine the point step interval and the traverse line spacing necessary to provide coverage of the whole area of the thin section, within the limit traversed by the mechanical stage. The point step interval and traverse line spacing has to be relevant to the grain size of the rock being examined. A mineral count of at least 600 points along a series of traverses of equal length and spacing is required; that is, the total number of points counted should exceed 600 by at least the number of points attributed to voids (vesicles, microcracks, pores and similar).AS 1141.26 pdf free download.
