Sampling Techniques - Day 3

Question 1

These are zones of increased content of
chemical elements in natural formations
associated with deposits of useful minerals.

Answer 1

Halos of Dispersion

Question 2

This arise in the surrounding rock with the formation of the mineral body

Answer 2

Primary halo

Question 3

Form in the products of decomposition of rock, and also in soil, water, plants, and the surface atmosphere as a result of supergene processes
taking place on the land surface

Answer 3

Secondary halo

Question 4

The four types of secondary dispersion halo

Answer 4

Mechanical Halos
Saline Halos
Gaseous Halos
Biogeochemical

Question 5

It is a sampling method where a specimen
is picked up from a portion of mineralized
outcrop/ore body.

Answer 5

Grab sampling

Question 6

The grab samples are taken and analyzed to obtain a preliminary idea about:

Answer 6

the nature and grade of whole deposit and appreciate metal content

Question 7

suitable sampling method for bedded, banded and vein type of deposits

Answer 7

Channel/Groove/Trench Sampling

Question 8

Channel/Groove/Trench Sampling method consists of cutting channels across the face of exposed ore and collecting ___________________ from each channel to make a sample

Answer 8

chips, fragments, and dust

Question 9

In conducting channel sampling, the outcrop is first:

Answer 9

cleared from unwanted materials

Question 10

T or F. Can rock faces be trimmed at the cutting point of the deposit?

Answer 10

True. Rock face may be trimmed if necessary.

Question 11

The location of the channel in channel sampling is market by:

Answer 11

a set of parallel lines

Question 12

The excavated material from channel sampling is collected, pulverized carefully, and the sampling site is:

Answer 12

labeled

Question 13

sampling method used for hard or uniform ores where it is difficult to cut channels

Answer 13

Chip or Point sampling

Question 14

In chip or point sampling, what material is being sampled?

Answer 14

blasted, broken material

Question 15

Chip or Point sampling are collected by using a small series of chips of rocks on a ___________ pattern from the working face in ____________ intervals.

Answer 15

regular grid pattern; regular intervals

Question 16

In chip or point sampling, the shape of the grid is adopted to the deposit’s

Answer 16

morphology and structure

Question 17

The main advantage of this sampling is its high productivity

Answer 17

Chip or Point Sampling

Question 18

Involves cutting of pieces of ore and rock from exposed faces
of ore and waste. The faces may be natural outcrops or faces
exposed in surface trenches and pits or in the backs, walls,
and floors of development openings and stopes.

Answer 18

Face or Muck or Lump Sampling

Question 19

In Face or Muck or Lump Sampling, face samples may be taken by either:

Answer 19

by cutting grooves or channels of uniform width and depth across the face or sections of the face or;
by picking off small pieces all over the face, more or less at random.

Question 20

This type of sampling method is used in checking of the
reliability of other types of samples and sometimes may be
taken to determine a correction factor for use in an estimate
based on samples of other types.

Answer 20

Bulk Sampling

Question 21

How are samples taken in bulk sampling?

Answer 21

by blasting down drift blocks or a section in a stope, or; obtaining a sample of several tons either from
trench, pit, channel or from the run-of-mine

Question 22

Collection and analysis of silt,
sand, mud, clay in a stream or
river bed, either dry or wet

Answer 22

Stream Sediment Sampling

Question 23

Usually employed as an early stage exploration tool to cover large areas relatively quickly in the hope of identifying smaller areas of interest to be followed up with prospecting and more detailed (and costly) sampling techniques.

Answer 23

Stream Sediment Sampling

Question 24

This method is more convenient for the determination of the deposit’s boundaries. Here, samples consists of the cuttings from drill holes.

Answer 24

Drill Hole Sampling

Question 25

What are the two types of errors

Answer 25

Random and Systematic

Question 26

What are the three common sampling patterns

Answer 26

Regular, Staggered, Equidistant

Question 27

Simplest grid design; all the samples are equally spaced apart vertically and horizontally

Answer 27

Regular Grid

Question 28

Samples are equally apart horizontally. Every other sample line is offset one half sample spacing which decreases the diagonal spacing between samples.

Answer 28

Staggered Grid

Question 29

Each sample has same distance of away from each surrounding sample. This pattern is sometimes called a triangular grid because 3 nearest samples form an equilateral triangle.

Answer 29

Equidistant Grid