| Feature (Landscape feature) |
| (or element) a component part of the landscape (eg hedge, wood, stream) |
| Feed |
| Material input to the crusher. |
| Field pattern |
| the pattern of hedges and walls that define fields in farmed landscapes. |
| Filler |
| Mixture of clay and silt in quarry fines which is usually waste material. |
| Filler grade |
| Specification of kaolin, calcium carbonate or other industrial minerals for use in papermaking, plastics and other applications. |
| Filter cake |
| Wet or dry solids produced by any filtration process, but usually applied in mineral processing to accumulation of wet solids in liquid filtering processes, especially filter presses. |
| Filter presses |
| Mechanical dewatering devices that hydraulically compress a filter pack comprising a series of diaphragms incorporating a porous cloth. A slurry is fed into the diaphragms under pressure. The filter pack is then compressed hydraulically expelling excess water through the cloth and leaving the desired solid material. |
| Fine material washer |
| Machine with three related functions: washing, dewatering, and classification. It consists of an inclined steel vessel with an internal screw which tumbles the water-suspended material, causing attrition and cleaning. Excess water drains off as the material passes up the vessel. It can also be called a sand screw. |
| Fines |
| Material < 0.06 mm (silt-grade material which often includes clays). Fines are usually present either as surface coatings or as clay bound agglomerates that need to be broken down. The fines content of a sand and gravel deposit is an important parameter in determining its economic viability. The fines content should not be greater than 25% for silt; this limit is lower for clay as it is harder to remove. |
| Fissure Flow |
| Groundwater which flows through a variety of fractures and fissures in a rock .
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| Flakiness |
| The proportion of flaky particle present in a product. Can also be referred to as the flakiness index. |
| Flakiness Index |
| An index of particle shape which indicates the proportion of flaky particle present in a product, often referred to simply as the flakiness. |
| Flocculants |
| Chemicals (usually charged polymers) used to promote aggregation of mineral particles in water and hence clarify suspensions as the particles are large enough to settle out under gravity. Both cationic polymers (containing positive charges) and anionic polymers (containing negative charges) are used for different applications. |
| Floodplain |
| A strip of relatively flat and normally dry land alongside a stream, river, or lake that is covered by water during a flood.
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| Flora Locale |
| Flora locale is a registered UK charity whose aims are to promote good practice in the use and sourcing of native flora for all projects that have wildlife in mind. www.floralocale.org |
| Fluidised bed classifier |
| Machine that sizes mineral particles by passing water through a suspension in a container. The effects of gravity and friction will separate the particles according to their density and particle shape. |
| Fluidised bed dryers |
| Machines used for drying, cooling and calcining of powders, crystals and granules. The materials float on a cushion of air or gas as a fluidised bed. |
| Flyrock |
| Flyrock is the name given to fragments of rock propelled into the air by the explosions. |
| Foliation |
| Parallel planar fabric in rocks caused by compression under metamorphic conditions which realigns the platy minerals such as clays and micas. |
| Forebays |
| A sediment forebay is a small pool located near the inlet of a slimes lagoon, storm basin or other stormwater management facility. These devices are designed as initial storage areas to trap and settle out sediment and dense pollutants before they reach the main basin. |
| Fragmentation (primary) |
| The breaking of solid rock into smaller fragments by the initial blast in a mine or quarry so that the bulk of the material is small enough to transport. |
| Fragmentation (secondary) |
| The breaking of oversize rocks following primary blasting to enable them to be transported to the primary crusher. This can be achieved by the use of explosives, a drop ball, or the use of hydraulic breakers (hammers or peckers). |
| Free Face |
When the first blast takes place, the only surface is the ground. Once some material has been excavated, there will then be a vertical surface (or face) as well, and so the rock now has space to expand and move in to during subsequent blasts. Ideally blasts should have two free faces in addition to the surface.
 Click to enlarge. |
| Frequency |
| The speed at which something vibrates, or how close the waves are to each other. Measured in the number of cycles per second or Hertz (Hz). |
| Frequency Response |
| A sensor used to measure vibration will not have the same sensitivity over the whole range of frequencies. This variation known as the frequency response can be determined and taken account of. |
| Frequency Spectra |
| Any vibration, whether it be through the ground or through the air, can be thought of as a combination of different amounts of lots of different individual single frequency vibrations. A single frequency vibration is termed a sine wave.
www.kettering.edu/~drussell/Demos/superposition/superposition.html. (Don?t worry about the equations, just look at the animations)
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| Fugitive Dust |
| Dust from an emission source that enters atmospheric suspension directly, without passing first through a chimney, stack or vent, such as windblow from a mineral storage pile. |