Natural History - Large Historic Cut & Polished Porphyry Slice.

Comprising lacquered porphyry slice of irregular shape, cut and polished on one side, probably recycled material mined in ancient Roman times between the 1st and 5th century A.D. 917 grams, 28 cm (11

A large pink agate crystal slice, polished on both faces; colour-enhanced. 484 grams, 23.5 cm (9 1/4 in.). From Antigas, Uraguay.Mineral Imports, London, UK.Gregory, Bottley & Lloyd (Gregory's). [No R

. With enhanced pink-colour and also showing translucent to opaque quartz crystals. 539 grams, 23.2 cm (9 1/8 in.). Ex Mineral Imports, London, UK. Gregory, Bottley & Lloyd (Gregory's). [No Reserve]

Found 2022 A.D. The cut and polished slice held in a custom-made collector's display box. 51 grams total, 84 mm wide including case (3 3/8 in.). From the Sahara Desert, North Africa. Property of a Sus

A cut and polished agate slice displaying crystals to the exposed inner surfaces; a naturally-occurring smiling face formed in the polished surface composed of two large circular eyes and a crescent-s

A cut and polished fluorite crystal obelisk with bands of green and purple colour. 240 grams, 13cm (5"). From a historic ‘Victorian Museum’ collection; from the stock of Gregory, Bottley & Lloyd (

A cut and polished fluorite crystal with bands of green and white colour. 175 grams, 90mm (3 1/2"). From a historic ‘Victorian Museum’ collection; from the stock of Gregory, Bottley & Lloyd (1981-

A large cut and polished sheet of snowflake obsidian with white spherulites of albite. From the historic ‘Victorian Museum’ and later collection of Gregory, Bottley & Lloyd (Gregory's); formerly G

A massive cut and polished agate slice showing bands of blue and brown colour to the border, honeycomb quartz crystals to the centre. From the historic ‘Victorian Museum’ or later collection of Gr

A large piece of cut and polished malachite with lustrous sheen of pale and dark green, pale crystals between nodules. From the historic ‘Victorian Museum’ or later collection of Gregory, Bottley

A group of six cut and polished agate geode slices; colour-enhanced. 322 grams total, 8.8-10.7 cm (3 1/2 - 4 1/4 in.). Mineral Imports, London, UK.Gregory, Bottley & Lloyd (Gregory's). [6, No Reserve]

A group of six polished agate geode slices; colour-enhanced. 396 grams total, 8.7-11.8 cm (3 3/8 - 4 5/8 in.). Mineral Imports, London, UK.Gregory, Bottley & Lloyd (Gregory's). [6, No Reserve]

Comprising three transparent slices showing attractive banding. 286 grams total, 9-14 cm (3 1/2 - 5 1/2 in.). Ex Mineral Imports, London, UK.Gregory, Bottley & Lloyd (Gregory's). [3, No Reserve]

Large group of cut and polished rocks and geode slabs. Sizes range from 2" to 9".

A pair of large prism cut fluorite polished points with bands of colour ranging from jade green, purple and clear, with 'rainbow' reflections in the body and at the points. From China; from the histor

Ordovician Period, 360 million years BP. A large cut and polished straight cephalopod Orthoceras sp. 295 grams total, 12.5cm (5"). From an old Lincolnshire collection 1980s; from Erfoud, Morocco, Nort

Triassic Period, 250-200 million years BP. A large slice of polished fossilised wood from Madagascar. 848 grams, 22cm (8 3/4"). Property of a Lincolnshire, UK, gentleman; acquired on the UK art market

. Comprising: anhydrate drilled core from Bahrain; an iridescent blue bornite; a rectangular cut wulfenite specimen; drilled calcite core; a polished red jasper slab found near Dunnotar Castle beach,

A fine, polished slice of rhodonite with a classic mix of red and black. From the historic ‘Victorian Museum’ and later collection of Gregory, Bottley & Lloyd (Gregory's); formerly Gregory, Bottle

Upper Cretaceous Period (Campanian), 76-75 million years BP. A large ammonite, from Fox Hills Formation, South Dakota, USA, cut and polished displaying the distinctive pattern of the cross-section cha

A group of six cut and polished circular malachite coasters with pale and dark green banding. From the historic ‘Victorian Museum’ or later collection of Gregory, Bottley & Lloyd (Gregory's); form

A group of five cut and polished amethyst obelisks or massage tools ranging in colour from light to dark purple and with rainbow reflections. From Brazil; from the historic ‘Victorian Museum’ or l

Devonian Period, circa 417-354 million years B.P. Cut and polished from a single fossiliferous block and each side set with a large Goniatite sp. specimen. 3.4 kg total, 15.3 cm high each (6 in.). Fro

A group of cut and polished smoky quartz obelisks with rainbow reflections. From Brazil; from the historic ‘Victorian Museum’ or later collection of Gregory, Bottley & Lloyd (Gregory's); formerly