THETB - Bircham Thetford-type ware

Pale to mid grey/buff, occasionally oxid core, very silty fabric with sparse quartz sand (clear and pink/black if oxid/reduced, ill-sorted, up to 0.5mm) and common v fine mica, sparse to moderate ?chalk (v fine to fine, up to 0.5mm) and moderate ferrous oxide of similar size (red if oxid, black if reduced), section sometimes streaky.

Thin-section description (H. Page): Very poorly sorted, rounded to sub-rounded, coarse sand to medium silt sized, equant quartz inclusions and rarer polycrystalline quartz, rare micritic calcite inclusions, and rare elongate muscovite mica and calcareous foraminifera microfossils. Strong bimodal grain size distribution indicating the use of sand temper. Homogeneous, optically inactive, light yellow-brown, calcareous clay matrix. Rare rounded sharp to merging textual features with a high optical density and rare dark brown clay streaks are also present. Rare micro-vesticles and vugh voids with common secondary calcite.