Sample
In archaeomagnetism, a piece or fragment of baked material taken in  an  in-situ baked structure.

Secular variation
The interior geomagnetic field is also a function of time. The field  slowly changes its direction and  intensity.  This  temporal  change  is  known  as secular variation. The secular variation has been discovered by the  English mathematician and astronomer H. Gellibrand (1597-1637) in 1634. The  secular variation can be graphically represented in a  Bauer-plot  (inclination  vs. declination),  named  after   L.A.   Bauer   (1865   -   1920).   Basis   of archaeomagnetic  dating. 


Specimen
Cylindrical or cubic  piece  cut  from  a  sample  by  drilling  or  sawing, respectively.

Spherical harmonics
The spherical harmonics are a common solution of the Laplace equation.  C.F. Gauss (1839) used them for  the  mathematical  description  of  the  global geomagnetic field. He could show, that the total Earth’s  geomagnetic  field is composed of external an internal fields  which  have  certain  geometries (magnetic  dipole,  magnetic  multipoles).  The  IGRF  model  is  based  on spherical harmonics.

Spinner magnetometer
Instrument to measure the remanent  magnetisation  of  rocks  based  on  the dynamo principle. The sample is rotated in the  centre  of  a  coil.  During rotation the field lines of the magnetic moment of the sample cut  the  coil and induce in it an electromagnetic force (signal) according to the  law  of Faraday. The amplitude of the signal is proportional to the magnetic  moment of the sample and  its  phase  determines  the  direction  of  the  magnetic moment.

SQUID-sensor
The SQUID sensor or  Superconducting  Quantum  Interference  Device  can  be regarded as a ring  with  superconducting  properties.  Once  a  circulating current I is stimulated in the ring, it flows for ever  as  the  resistivity is nearly zero and the current can  only  be  changed  through  an  external magnetic field (from a sample). When the external magnetic field  is  strong enough, the circulating current  reaches  a  critical  value  Ic,  the  SQUID becomes resistive, magnetic flux enters the ring and the  current  drops  by quantised values ΔI = nΦ0 (nΦ0 denotes multiples of the flux  quantum  Φ0  = ħ/2e = 2.07 ( 10-15, ħ = Planck’s constant and e =  electron  charge)  below Ic. As the current dropped below Ic, the superconducting state  is  achieved again. Further increase of the external magnetic field yield  multiple  flux changes. A critical current equal to 0.75Φ0, causes the circulating  current to change polarity. The number of polarity changes is  proportional  of  the magnetic  field  produced  by  the  sample  and  hence   to   its   remanent  magnetisation.

Stokehole
Part of a kiln. A hollow dug into the ground from which fuel was put into the  fire  burning in the combustion chamber. Also called stoke-pit. If the kiln  is  built  at the surface one can speak about a stoking area.

Stone-age
Denotes a time period in the early development of the human  society  before the use of metals, Weapons and tools were made from stone. Began  in  Europe around 2 million years ago and ended around 4000 BC. It  can  be  subdivided in three periods Palaeolithic, Mesolithic and Neolithic.

Superparamagnetism
Ferromagnetism of very small particles (in the order of  30  nm and smaller)  that  have relaxation times on the laboratory time scale.

Superstructure
Free-standing temporary or permanent walling of the kiln above  the  ground, this term applies also to the kiln structure above the level of  the  raised oven-floor.

Support
Protruding, recessed or raised structure, temporary or  inbuilt  located  in the combustion chamber of a kiln, to support  the  mechanical  stability  of the overlying raised oven-floor. If located in the centre  of  the  kiln  as single standing element, also called pedestal.