An almost spherical geode with brown and grey banding, the internal cavity filled with deep coloured amethyst crystals and clusters of grey calcite. 520 grams total, 80-82 mm



From Brazil. Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's), Harwich, UK.

Platyostoma niagarensis set on an irregular matrix. 242 grams, 92 mm



Acquired Hunstanton, UK. From the private collection of Kenneth Machin (1936-2020), Buckinghamshire, UK; his collection of antiquities and natural history was formed since 1948; thence by descent.

From Carcharocles megalodon polished, showing some good enamel. 369 grams, 11.9 cm



From Aurora, North Carolina, USA. From the private collection of Kenneth Machin (1936-2020), Buckinghamshire, UK; his collection of antiquities and natural history was formed since 1948; thence by descent.

Carcharodon megalodon is regarded as one of the largest and most powerful marine predators in vertebrate history and likely had a profound impact on structuring of the marine communities. Fossil remains indicate that this giant shark reached a length of more than 16 metres (52 ft) and also affirm that it had a cosmopolitan distribution. Scientists suggest that in life it looked like a stockier version of the great white shark, Carcharodon carcharias.

Comprising thirty-one necklaces with oblate and tubular beads in lapis lazuli, serpentine, steatite and other stones. 313 grams total, each app. 46 cm long



Ex property of a London, UK, gentleman; acquired from his father's collection. Property of a Californian, USA, collector.

Each with one polished face displaying mainly brown and grey banding. 1.98 kg total, 61-74 mm



From Brazil. Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's), Harwich, UK.

A freestanding geode section lined with vibrant prismatic amethyst crystals. 648 grams, 99 mm



From a Lincolnshire, UK, collection.

Cut to a heart shape and polished to reveal the internal structure. 114 grams, 68 mm



From a Cambridgeshire, UK, collection.

A cut and polished slice with inked find location to the edge; in a Swiss membrane box with aluminium identification label and dealer's card. 27.12 grams, 55 mm



Found Charente, France. Ex Robert Haag collection, Tucson, AZ, USA. From a Leicestershire, UK, collection.

Comprising a Goniatite sp. and a Orthoceras sp. set on a freestanding textured matrix. 946 grams, 15.9 cm



From Atlas Mountains, Morocco, North Africa. From a Cambridgeshire, UK, collection.

Comprising two matrices with a Petraster sp. specimen on each with some other fossil remains. 660 grams total, 13-13.6 cm



From a Cambridgeshire, UK, collection.

Comprising five necklaces, each with graduated mainly tubular amethyst beads with floral gold-coloured spacers, three with a tabular centrepiece; restrung. 385 grams total, 57-73 cm



Ex property of a West London gentleman; his collection formed in the late 1980s-early 1990s. Property of a Californian, USA, collector.

Comprising two Otodus obliquus teeth on individual matrices. 705 grams total, 10.3-14.3 cm



From a Cambridgeshire, UK, collection.