Reference number  
DRS 93 -3: 20 16 
© RBS yyyy 
© RSB 201 6 
 
 DRAFT R WANDA 
STANDARD  DRS 
96-3 
 
Second  edition  
2016-mm-dd 
Aggregates  —Test methods  
Part 3: 
Methods for sampling  
  DRS 96 -3: 201 6 
©RSB 2016  All rights reserved                  ii 
 
 In order to match with technological development and to keep continuous progress in industries, 
Standards are subject to periodic revi ew. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
 
 
© RSB 2016 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanic al, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce this document should be addressed to  
Rwanda Standards Board . 
P.O Box 7099 Kigali -Rwanda  
Tel. +250 252 586103/ 582945/ 582946  
Fax + 25 0 252 583305  
E-mail: info@rbs.org.rw  
Website:www.rsb.gov.rw  DRS 96 -3: 2016  
iii                 ©RSB 2016 All rights reserved  
 
 Contents  Page  
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Terms and d efinitions  ................................ ................................ ................................ ...........................  1 
3 Significance and use  ................................ ................................ ................................ .............................  2 
6 Procedure for sampling coarse, fine and all -in aggregates  ................................ ..............................  4 
7 Sample reduction  ................................ ................................ ................................ ................................ .. 7 
7.1 General  ................................ ................................ ................................ ................................ ...................  7 
7.2 Using a sample divider.  ................................ ................................ ................................ ........................  8 
7.3 Quartering  ................................ ................................ ................................ ................................ ..............  8 
7.4 Sample reduction to provide replicate samples.  ................................ ................................ ...............  8 
8 Nominal description  ................................ ................................ ................................ ..............................  8 
9 Dispatch of samples  ................................ ................................ ................................ ..............................  9 
9.1 Packing samples of aggregates  ................................ ................................ ................................ ...........  9 
9.2 Informat ion to be sent with samples.  ................................ ................................ ................................ .. 9 
10 Certificate of sampling  ................................ ................................ ................................ ..........................  9 
Annex  A (informative)  Petrological description of natural aggregates  ................................ .....................  10 
Annex  B (informative) Recommended form of certificate of sampling  ................................ ......................  12 
Annex C (informative) Description of particle shape  and su rface texture of aggregates  ........................  13 
 DRS 96 -3: 201 6 
©RSB 2016  All rights reserved                  iv 
 
 Foreword  
Rwanda Standard sareprepared by Technical Committees and approved by Rwanda Standards Board of (R SB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Anne x 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards 
adopted by Technical committ ees are ratified by me mbers of RSB Board of Director s for publication and 
gazett ement as Rwanda Standards.  
DRS96-3:2015 was prepared by Technical Committee RSB/TC09, Building Materials and Civil Engineering . 
In the preparation of this standard, reference was made to the following standard:  
ASTM  D75/D75M − 14 Standard practice for sampling aggregates  
IS 2430 : 1986 ( Reaffirmed 2005 ) Methods for sampling of aggregates for concrete  
KS 1238 -3:2003 ,Methods of testing aggregates Part 3:Method for sampling  
The assistance de rived from the above source i s hereby acknowledged with thanks.  
Committee membership  
The following organizations were represented on the Technical Committee on Building Materials and Civil 
Engineering (RSB/TC 09) in the preparation of this standard.  
University of Rwanda/CST  
Rwanda Hous ing Authority  
Ruliba Clays Ltd  
IPRC Kigali  
Entreprise Mubiligi Paul  
Rwanda Public Procurement Authority  
Rwanda Standards Board — Secretariat  
 DRS 96 -3: 2016  
v                 ©RSB 2016 All rights reserved  
 
 Introduction  
All the stages of sampling leading to the production of proper test portions require skill and care. Problems of 
several kinds arise.  
a) Sampling may expose the operator to difficulty and possible danger. Due considerations should be given 
to the safet y of the operator at all times. Sampling within the body of a vehicle or under chutes pose 
particular difficu lties. 
b) Often it is not easy to discern a batch, and thus specifications that rely on this standard should state the 
maximum quantity that a sample should represent.  
c) Aggregates often segregate by size and, ideally, they should be sampled from large quantiti es during 
loading or unloading, but this is often impractical.  
The method set out in Clause 5 shoul d be used as the basis for tests for compliance with specifications for 
aggregates.  
The definitions of the several stages in the production of the test porti ons are given in Clause 2. In some 
cases the bulk sample is inconveniently large to send for testing and has to be reduced. If not, it becomes the 
laboratory sample.  
At the laboratory, the laboratory sample is reduced to the test portions required. If adeq uate facilities exist at 
the point of taking the bulk sample, all necessary reduction to the stage of producing the test portions may be 
done before dispatch to the laboratory. If several kinds of tests are to be done, an intermediate stage of 
reduction is  necessary. In other cases, the test portion is reduced directly from the laboratory sample. It is 
again emphasized that care has to be taken to ensure that the test portions are representative of the bulk 
sample.  
   DRS 96 -3: 2016  
1                 ©RSB 2016 All rights reserved  
 
 Aggregates  — Test m ethods— Part 3:Method s for sampling  
1 Scope  
This part  of DRS 96specifies methods for obtaining samples of aggregates of the quantity required for carrying 
out testing in accordance with other parts of DRS 96.The method to be used for recording the nominal 
description of material s sampled is also given.  
This standard  covers samplin g of coarse and fine aggregates for the purpose of p reliminary investigation of 
the potential source ofsupply,  control of the product at the source of supply, control of the operations at the 
site of use , and  acceptance or rejection of the materials.  
NOTE 1  Sampling plans and acceptance and control tests vary with the type of construction in which the material is 
used.The quality of the results produced by this standard are dependent on the competence of the personnel performing 
the procedure and the capability, calibration, and maintenance of the equipment used . 
2 Terms and definitions  
For the purposes of this standard, the follow ing terms and definitions apply . 
2.1  
aggregates  
crushed stone, crushed boulde rs, gravel, sand, industrial by -produc ts or such other inert material  
 
 
2.2  
fine aggregates  
 aggregates most of which pass through 4.75 mm sieve and they include natural sand, crushed stone 
sand,and crushed gravel sand  
 
2.3 
coarse aggregates  
 aggregates  most of whic h are retained on 4.75 mm sieve  
 
2.4 
all-in aggregates  
material composed of fine a ggregates and coarse aggregates  
 
2.5  
batch 
the quantity of aggregates of the same class, nominal size,source and offered for inspection at one time. The 
batch may consist of the whole or a part of the quantity ordered for a definite quantity of some commodity 
manufactured or prod uced under conditions which are presumed  uniform  
NOTE  With a continuous process ,the quantity produced during a specified period should be treated as a batch.  
2.6  
increment  
a quantity of aggregates  taken  by a sampling device  at one time  from a larger body of aggregates   
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 NOTE  When sampling aggregates, the aggregates  taken by a single operation of the scoop should be treated as a 
sampling in crement.  
2.7  
bulk sample  
an aggrega tion of the sampling increments  
2.8  
laboratory sample  
a sample intended for l aboratory inspection or testing  
2.9  
test porti on  
the material used as a  whole in testing or inspection  
NOTE  When sampling a batch of aggrega tes, the aggregation of the sampling increments yields the bulk sample. If 
the bulk sample is of an appropriate size it is sent to the laboratory as a laboratory sample, otherwise it is reduced by a 
sample reduction process as described in Clause 6 to the laboratory sample. At the laboratory, the laboratory sample is 
reduced by one or more reduction operations to the quantity required by a particular test method; the quantity of material 
produced at the final stage of sample reduction is referred to as the test portion. A particular test method may then require 
several specimens to be made from a test portion.  
3 Significance and use  
3.1 .Sampling is equally as im portant as the testing, and the sampler shall use every precaut ion to obtain 
samples that show the nature and condit ion of the materials which they represent.  
3.2  Samples for preliminary investigation tests shall be  obtainedby the party responsible f or development of 
the potential source . Samples of materials for control of the production at the source  or control  of the work at 
the site of use shall be  obtained by the manufacture r, contractor, or other parties responsible for 
accomplishing th e work. Samples for tests to be used in acceptance or rejection  decisions by the purchaser 
shall be obtained by t he purchaser or his authorized competent representative.  
NOTE 2  The preliminary investigation and sampling of potentialaggregate sources and types occupies a very  important 
place in determining the availability and suitability of the larg est single constitu ent entering into the construction. It 
influences th e type of construction from the standpoint of economics and governs th e necessary material control to ensure 
durability of the resulting structure, from the aggregate standpoint .This investigation should be done only by a 
responsible trained andexperienced person.  
4 Securing samples  
4.1  General  
Where practicable, samples to be tested forquality shall be obtained from the finished product. Samplesfrom 
the finished product to be tested for abrasion loss sh all notbe subject to further crushing or manual reduction 
in particle size in preparation for the abras ion test unless the size of the finished product is such that it  
requires further reduction for testing purposes.  
   DRS 96 -3: 2016  
3                 ©RSB 2016 All rights reserved  
 
 4.2  Inspection  
The material to be sam pled shall be visuallyinspected to determine discernible  variations. If any discernible 
variations are noted, corrective action shall be  taken to establish homogeneity in the mater ial prior to 
sampling. If it is necessary to indicate the degree  of variabil ity existing within the main pile, separate sampl es 
shall be drawn from separate areas of the pile. The seller shall provide suitable eq uipment needed for proper 
inspection and sampling.  
4.3  Procedure  
4.3.1 Sampling from a flowing aggregate stream (Bins o r Belt discharge)  
 Select units to be sampled by a randommethodfrom the production. ; 
 Obtainat least three approximately equal increments, selected atrandom from the unit being sampled, 
and combine to form afield sample ;and 
 Take each increment from the entir e cross section of the material as it is being discharged. It is 
usually necessary to have a special device constructed for use at each particular plant. This device 
consists of a pan of sufficient size to intercept the entire cross section of the discharg e stream and 
hold the required quantity of material without overflowing. A set of rails may be necessary to support 
the pan as it is passed under the discharge stream. Insofar as is possible, keep bins continuously full 
or nearly full to reduce segregation . 
NOTE  Sampling the initial discharge or the final few tons from a bin or conveyor belt increases the chances of 
obtaining segregated material and should be avoided . 
4.3.2  Sampling from the conveyor belt 
 Select units to be sampled by a random method fromt he production. Obtain at least three 
approximately equalincrements, selected at random, from the unit being sampledand combine to form 
a field sample ;  
 Stop the conveyorbelt while the sampl e increments are being obtained;  
 Insert two templates, the shape of  which conforms to the shape of the belt in the aggregate str eam on 
the belt  and space them such that the material contained between them yield s an increment of the 
required weight ;and 
 Carefully scoop all material between the templates into a suitable cont ainer and collect the fines on 
the belt with a brush and dust pan and add to the container.  
4.3.3  Sampling from stockpiles  
Avoid sampling coarseaggregate or mixed coarse and  fine aggregate from stockpiles whenever possible, 
particularl y when the sampling is done for the purpose of determining a ggregate properties that may be 
dependent upon the grading of the sample. If circumstances make it necessary to obtain sam ples from a 
stockpile of coarse aggregate or a stockpile of comb ined coarse and fine aggregate , design a sampling plan 
for the sp ecific case under consideration to ensure that segregation d oes not introduce a bias in the results. 
This approach will all ow the sampling agency to use a sampling plan that will give a confidence in results 
obtainedthere from that is agreed upon by all parties concerned to be acceptable for the particular situation. 
The sampling plan shalldefine the number of samples necessary to represent lots andsublots of specific sizes. 
The sampling plan shall also defineany specialized  site-specific sampling techniques or proceduresthat are 
required to ensure unbiased samples for existingconditions. The owner and suppl ier shall agree upon the use 
of any specialized site -specific  techniques or procedures.   
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 5 Apparatus  
5.1 A small scoop , to hold a volume of at least 1 L (i.e. abou t 155 kg of aggregate of normal density).This 
scoop is used for sampling aggregates of nominal sizes less than 5 mm.  
5.2 A large scoop , to hold a volume of at least 2 L (i.e. about 3 kg of aggregate of normal densi ty).This 
scoop is used to sample any grading of aggregate, but is required particularly for aggregates of nominal sizes 
greater than 5 mm.  
NOTE  A suitable scoop  is shown in Figure 1.  
5.3 Containers , clean and non -absorbent, such as buckets, for collecting the increments of a sample  
5.4 Containers , clean and impervious, such as bags made of plastics at least 100 m thick, for sending 
samples to laboratories  
5.5 A sample divider , appropriate to the maximum size to be handled, e.g. a riffle box such as that 
illustra ted in Figure 2. Alternatively, a flat shovel and a clean flat and hard surface, e.g. a metal tray, for use in 
quartering.  
NOTE  For sampling  in special circumstances other apparatus may be needed.For example, shovels, spades, picks, 
etc. may be neede d to reach the material to be sampled.  
6 Procedure for sampling coarse, fine and all -in aggregates  
6.1 The quantity of material to be represented by the bulk sample shall be clearly defined and the sample 
shall be taken by a responsible and experienced perso n. 
6.2 Obtain a bulk sample by collecting, in the clean containers, a sufficient number of increments (i.e. 
scoopfuls) to provide the required quantity of aggregate for all the tests subsequently to be made. However 
the number of increments shall be not le ss than those given in Table 1.  
6.3 Take the increments from different parts of the batch in such a way as to represent the average quality.  
6.4 When replicate samples are required , take each sample as a separate and independent operation.  
6.5 When samplin g from heaps of aggregate, take the required number of increments from positions evenly 
distributed over the whole surface of the heap. At the required spot for each increment remove as much 
surface material as necessary to expose aggregate at least 150 mm  in from the surface. Take the increment 
by digging the scoop into this exposed material.  
NOTE 1 Aggregates that are badly segregated present problems of varying complexity and in many cases it is better to 
wait until they are moved.  
NOTE  2 Sampling near gr ound level should be done with care to avoid contamination with, for example, residues of 
previous materials.    DRS 96 -3: 2016  
5                 ©RSB 2016 All rights reserved  
 
 Table 1  — Minimum number of sampling increments  
Nominal size of 
aggregate  Minimum number of sampling 
increments  Approximate minimum mass for 
norma l density aggregate  
Large scoop  Small scoop  
28 mm and larger  20 - 50 Kg 
5 mm to 28 mm  10 - 25 Kg 
5 mm and smaller  10 half scoops  10 10 Kg 
 
6.6 When sampling from material in motion, i.e. when it is being loaded or unloaded, calculate the sampling 
times to give the required number of sampling increments, ensuring that they are randomly distributed through 
the batch of aggregate.  
6.7 When sampling from a falling stream of aggregate, take increments from the whole width of the stream.  
NOTE  Mechanical sa mplers, manually or automatically operated, used for sampling from moving streams may be 
taken as being in accordance with this standard provided that each complete operation of the sampler produces an 
increment of at least 2 L of coarse or all -in aggregat e or 1 L of fine aggregate.  
6.8 When sampling from conveyor belts, stop the conveyor at the appropriate time and take all the material 
from a fixed length of conveyor.  
NOTE  Never sample  manually from a moving conveyor.  
6.9 For all methods of sampling, comb ine all the increments and either dispatch the bulk sample or reduce 
it to a smaller representative sample, acceptable to the tester, by the procedure described in Clause 7 and 
then dispatch this smaller sample for testing.  The sample dispatched to the la boratory is the laboratory 
sample  
6.10 On completion of the sampling process, always make a visual check of the relation of the sample to the 
material in bulk.  
NOTE 1 Whether  the bulk is uniform or not, the sample should be seen to contain a similar range o f sizes including the 
maximum and minimum.  
NOTE 2 The procedure described in this clause is for obtaining a bulk sample representative of the batch sampled.  
When sampling is carried  out to assess variability within a batch, a number of increments are taken  from defined places in 
the batch and arenot combined but tested separately. For routine testing quality control, simplified procedures may be 
used. Fewer increments may prove satisfactory for this purpose. Where it is necessary to determine the presence a nd 
quantity of an occasional contaminant, special measures may be necessary and reference should be made to the 
appropriate Part of this standard. These and other departures from the method should be recorded on the certificate of 
sampling.   
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  DRS 96 -3: 2016  
7                 ©RSB 2016 All rights reserved  
 
  
7 Sample redu ction  
7.1 General  
It is sometimes necessary to reduce the mass of the b ulk sample substantially.  This shall be done in such a 
way as to preserve at each stage a representative part of the bulk sample. The methods described in 7.2 and 
7.3 are acceptable.  
 
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 7.2 Using a sample divider.  
The width of the channels of the divider shall be appropriate to the maximum particle size of the aggregate 
and, in general, not less than 1.5 times the size of the largest aggregate particle. When the aggregate 
contains material finer th an 5 mm it shall be surface dry. Thoroughly mix and then pass it through the sample 
divider.  Retain one portion; pass it through again and repeat the process as often as necessary to reduce the 
original sample to the required mass.  
7.3 Quartering  
Thoroughly m ix the sample by heaping it on to a clean, flat and hard surface to form a cone, and turning this 
over with a shovel to form a new cone, the operation being carried out three times. Form each conical heap by 
depositing each shovelful  of the material on the  apex of the cone so that the portions which slide down the 
sides are distributed as evenly as possible, and so that the center of the cone is not displaced.  
Flatten the third cone by repeated vertical insertion of the shovel across the apex of the cone, l ifting the shovel 
clear of the material after each insertion.  Then quarter the flattened heap, which shall be uniform in thickness 
and diameter, along two diameters intersecting at right angles.  Discard one pair of diagonally opposite 
quarters and shovel  the remainder into a heap.  Repeat the process of mixing and reduction, until the required 
mass of sample is obtained.  
7.4 Sample reduction to provide replicate samples.  
When duplicate (or more) laboratory samples are required from bul k sample, first reduce t he bul .sample by 
the procedure described in 7.2 or 7.3. Reco mbine all the excess bulk sample rejected at the individual division 
stages, mix thoroughly and reduce again to provide a second laboratory sample. Repeat as necessary to 
provide the required numb er of laboratory samples . 
NOTE  The procedure should also be used to provide replicate test portions from a laboratory sample.  
8 Nominal description  
The nominal description of the material sampled shall be recorded on the certificate (see Clause 10) under the  
following general headings : 
a) Type  
Use o ne of the following terms:  
1) ‘crushed rock’;  
2) ‘sand  or ‘gravel’ : in this case record if the aggregate is crushed or partially crushed and, when 
known, if it has been obtained by inland working;  and 
3) ‘artificial’ : in this c ase, record if the artificial aggregate is slag, synthetic or broke n rubble,etc  
b) nominal size; and    DRS 96 -3: 2016  
9                 ©RSB 2016 All rights reserved  
 
 c) otherreferences shall be made to the presence of any obvious extraneous pieces in the sample such as 
clay lumps, organic material, etc.  
NOTE  1 When a geologic al or petrological term is required to describe an aggregate in more detail, it should be 
provided by a competent person or authority using, whenever possible, a term from A nnex A.Similarly, when a 
metallurgical term is required to describe a slag in more de tail, it should be provided by a competent person or authority.  
NOTE  2 Annex  C should be used when it is necessary to describe the particle shape and surface texture 
characteristics.  
9 Dispatch of samples  
9.1 Packing samples of aggregates  
The samples shall be tr ansferred completely to containers (see 5.4) which shal l then be sealed for dispatch. 
Where necessary, particularly where the aggregate contains crushed particles of the larger sizes, the bags 
shall be protected against damage in transit by casing in suita ble containers.  
NOTE  Individual packages should preferably not exceed 30 kg.  
9.2 Information to be sent with samples.  
Each package shall contain a card, suitably protected from damage by moisture and a brasion, giving the 
name and address of the sender and his /her description of the material. When several samples are taken from 
a single source, each individual sample shall be separately identified.  
10 Certificate of sampling  
Each sample, or group of samples from a single source, shall be accompanied by a certificat e, from the 
person responsible for taking the sample, certifying that sampling was carried out in accordance with this 
standard. The  certificate shall include as much as is appropriate of the following information. See A nnex  B for 
a recommended form of cer tificate . 
a) the date, time, place and method of sampling;  
b) the name and location of source;  
c) sample identification tag (or tags);  
d) all the data recorded under nominal description (Clause 8). When a geological, petrological or 
metallurgical term is used to desc ribe a material, the identity of the competent person or authority 
responsible for the description shall be recorded;  
e) description of the batch;  
f) any other information likely to be helpful to the tester (see NOTE 2 to paragraph 6.10); and 
g) name and signature of  sampler.   
©RSB 2016  All rights reserved                  10 
 
 Annex  A 
(informative ) 
 
Petrological description of natural aggregates  
A.1 The aggregate should be described by an appropriate petrological name, preferably selected from the 
list of terms and definitions given in Table  A.1. In the event that the aggrega te cannot be described adequately 
by those terms, it should be described by another appropriate petrologically accepted term.  
A.2 In the case of sedimentary rocks such as limestone or sandstone the geological age of the rock should 
also be given. The geolo gical age requirement is satisfied by using one of the following terms:  
a) precambrian ; 
b) cambrian ; 
c) ordovican ; 
d) silurian ; 
e) devonian ; 
f) carboniferous ; 
g) permian ; 
h) triassic ; 
i) jurassic ; 
j) cretaceous ;and 
k) tertiary.  
For example :different types of limestone are described in te rms of their age as follows: Carboniferous limestone, Jurassic 
limestone, Silurian limestone etc. The age of post -Tertiary materials need not be given.  
NOTE  The term Magnesian Limestone can be substituted for Permian Limestone where appropriate  
A.3 Where t he petrological character of an aggregate is intermediate between any of the terms in Table 2, 
or, where it consists of mixed gravels, the aggregate should be described by combining appropriate terms, 
Example:  granite/diorite, basallt/dolerite, microgranit e/rhyolite, quartzite/granulite, flint/ quartzite.Petrological 
description does not take account of suitability for any particular purpose .   DRS 96 -3: 2016  
11                 ©RSB 2016 All rights reserved  
 
 Table A1— Rock types commonly used  for aggregates  
Petrological term  Description  
andesite  a fine grained, usually vo lcanic, variety of diorite  
arkose  a type of sandstone or gritstone containing over 25 % feldspar  
basalt  a fine grained basic rock, similar in composition to gabbro, usually volcanic  
breccia† rock consisting of angular, unworn rock fragments, bonded by n atural cement  
chalk  a very fine grained Cretaceous limestone, usually white  
chert  cryptocrystalline‡ silica  
conglomerate  rock consisting of rounded pebbles bonded by natural cement  
diorite  an intermediate plutonic rock, consisting mainly of plagioclas e, with hornblende, augite or biotite  
dolerite  a basic rock, with grain size intermediate between that of gabbro and basalt  
dolomite  a rock or mineral composed of calcium magnesium carbonate  
flint cryptocrystalline silica originating as nodules or layer s in chalk  
gabbro  a coarse grained, basic, plutonic rock, consisting essentially of calcic  
plagioclase and pyroxene, sometimes with olivine  
gneiss  a banded rock, produced by intense metamorphic conditions  
granite  an acidic, plutonic rock, consisting es sentially of alkali feldspars and quartz  
granulite  a metamorphic rock with granular texture and no preferred orientation of the minerals  
greywacke  an impure type of sandstone or gritstone, composed of poorly sorted fragments of quartz, other minerals 
and rock; the coarser grains are usually strongly cemented in a fine matrix  
gritstone  A sandstone, with coarse and usually angular grains  
hornfels  A thermally metamorphosed rock containing substantial amounts of rock -forming silicate minerals  
limestone  a sedimentary rock, consisting predominantly of calcium carbonate  
marble  a metamorphosed limestone  
microgranite  an acidic rock, consisting predominantly of calcium carbonate  
quartzite  a metamorphic rock or sedimentary rock, composed almost entirely of qua rtz grains  
rhyolite  a fine grained or glassy acidic rock, usually volcanic  
sandstone  a sedimentary rock, composed of sand grains naturally cemented together  
schist  a metamorphic rock in which the minerals are arranged in nearly parallel bands or layers. Platy or elongate 
minerals such as mica or hornblende cause fissility in the rock which distinguishes it from a gneiss  
slate  a rock derived from argillaceous sediments or volcanic ash by metamorphism, characterized by cleavage 
planes independent of the or iginal stratification  
syenite  an intermediate plutonic rock, consisting mainly of alkali feldspar with plagioclase, hornblende, biotite, or 
augtite  
trachyte  a fine grained, usually volcanic, variety of syenite  
tuff consolidated volcanic ash  
NOTE  1 The terms microgranite , rhyolite, andesite, or trachyte, as appropriate, are preferred for rocks alternatively described as 
porphyry or felsite.  
NOTE  2 Some terms refer to structure or texture only e.g. breccia or conglomerate, and these terms cannot be used a lone to 
provide a full description.  
NOTE  3 Composed  of crystals so fine that they can be resolved only with the aid of a high power microscope.   
©RSB 2016  All rights reserved                  12 
 
 Annex  B 
(informative ) 
Recommended  form of certificate of sampling  
The form of certificate of sampling is shown in tabl e B1.  
Table B1 —Form of certificate of sampling Table B1 —Form of certificate of sampling  
Certificate of sampling in accordance with DRS 96, Part 3  
Sample identification tag:  
Description of the sample/ batch  
 
Sampling details  
                (a)  Date:  
                (b) Time:  
                (c) Place:  
                (d) Method:  
                (e) Name and location of source:  
                (f) Quantity of batch sampled:  
 
Nominal description:  
 (a) Type :(i) Crushed rock      (ii) Artificial   (iii) Natural  
 (b) Nominal size:  
 (c) Comments on sample:  
                (d) Coarse or fine aggregate:  
 
Any departure from this standard:  
Sampling Organization:   
Name and signature of sampler:  
   DRS 96 -3: 2016  
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 Annex C  
(informative)  
Description of particle shape  and surface texture of aggregates  
To avoid lengthy descriptions, it is convenient to classify aggregate particles shape and surface texture 
characteristics under a number of simple headings.  The system given in Tables C1 and 2is devised for this 
purpose . 
Table C1 — Particle shape  
Classification  Description  
Rounded  Fully water -worn or completely shaped by attrition  
Irregular  Naturally irregular, or partly shaped by attrition and having rounded 
edges  
Angular  Possessing well defined edges formed at the int ersection of roughly 
planer faces  
Flaky  Having one dimension significantly smaller than the other two dimensions  
Elongated  Having one dimension significantly larger than the other two dimensions  
Flaky and elongated  Having three significantly larger than  width and width significantly larger 
than thickness  
Table C2— Surface texture  
Surface texture  Characteristics  
Glassy  Conchoidal (i.e. curved) fracture  
Smooth  Water -worn or smooth due to fracture of laminated or very finely grained 
rock 
Granular  Fractu re showing more or less uniform size rounded grains  
Rough  Fracture of fine or medium grained rock containing no easily visible 
crystalline constituents  
Crystalline  Containing easily visible crystalline constituents  
Honeycombed  With visible pores and ca vities  
NOTE  1 Surface texture has been described under the above six headings.This grouping broad, being based on the 
impression which would be gained by visual examination of hand specimens. It does not purport to be precise petrological 
classification ( see Annex  A). Different specimens of the same rock type may not fall into the same group in Table . 
 
DRS 96 -3: 2016  
ICS 91.100.15  
 
©RSB 2016  All right s reserved