This edge-ground stone axe is made from porphyritic andesite.  It dates to the Neolithic period, ca. 4350-6000 BP, and was found in the Freugh-Stanraer region of southwestern Scotland.
The artefact is curated by the Australian Institute of Archaeology, catalogue no. IA24.201. 

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The axe in this model was made from a fine-grained igneous stone.  The term ‘porphyritic’ refers to igneous stones where the crystals (or ‘phenocrysts’) can be seen with the naked eye.  In this artefact, the crystals are dark speckles against the lighter-coloured background of fine-grained andesite.  The crystals are a mineral known as ‘plagioclase’, a type of feldspar.  Even though it is usually difficult to flake, porphyritic andesite was often chosen for making stone axes because edge-grinding can produce a tough and easily resharpened cutting edge.  An extensive Neolithic porphyritic andesite quarry is present on Lambay Island, off the east coast of Ireland.  The manufacturing process was usually done by pecking and rough percussion flaking in the early stages, although most signs of this were  mostly eliminated by grinding in the production of this axe.  The short length of this axe suggests that it was resharpened many times prior to discard.  The surfaces of the tool are highly polished.

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Stone axes appear in the European Mesolithic period by about 10,000 BP and proliferated during the Neolithic, from about 3700 to 7500 BP.  Hundreds of thousands of stone axes have been found across Europe, and they are one of the most common tool types of the Neolithic.  Most researchers believe that they were an essential tool for clearing forests for agriculture.  An array of different axe forms were made and used across this period, but most varieties had cutting edges produced by grinding—referred to in Europe as ‘polished’ axes.  Some types were completely ground across all of their surfaces, while the grinding on others was limited to the cutting edge.  Grinding was a laborious process, particularly on flint axes.  Cross sections ranged from rectangular to lenticular or nearly round, and axes varied considerably in shape and size.  Axes of prized stone were traded widely between Neolithic groups across Europe.  
Axes were set into a hole made in a wood shaft handle.  Because the axes tapered backwards from the cutting edge, they wedged into the hole with use.  Several stone axes have been recovered from sites with the handle still intact.  An ‘axe’ was hafted with the cutting edge parallel to the shaft, and an ‘adze’ was hafted with the cutting edge at right-angles to the shaft.  The edge is centred on an axe, but offset from the centre on an adze.  
Stone shaft-hole axes (or ‘battle axes’), usually made of igneous or metamorphic stones, appeared by about 4800 BP and persisted into the Bronze Age.  These were often ornate in shape and were perforated to receive a relatively thin wood handle.  The perforation was drilled using a hollow bone or wood.  Stone axes with pecked grooves (‘saddle-grooved’ axes) were made and used during the Bronze Age in Bavaria alongside metal axes, and grooved stone axes were used to mine and process copper ore in southern Italy. 
Large  ‘prestige’ axes, often expertly made of spectacular stones, were interred in graves or buried together in caches.  While some caches included only unused prestige axes, others included axes in all stages of use and repair.  In Denmark alone, 171 caches, comprising about 500 axes, have been found and reported.  One author notes that, in Sweden, stone axes ‘were deposited in almost every single bog’, probably as part of ritual activity.  These various patterns suggest that axes were not only functional tools, but were also important in a social context.  Their symbolic importance continued into the more recent past: ancient stone axes were collected from archaeological sites since Medieval times as amulets that provided protection to life and property.