USE OF COLOR IN MINERAL IDENTIFICATION

In some minerals color is directly related to a metallic element, is characteristic, and can be useful in identification. As examples,  azurite as shown in Figure 1A, is always blue due to the presence of copper, and rhodochrosite, shown in Figure 1B, is always pink to red due to the presence of manganese,. However minerals. . . Read More

USE OF CRYSTAL FORMS AND HABITS IN MINERAL IDENTIFICATION

The atoms within the crystal of a mineral are arranged in a regular fashion to form a lattice, and the crystal exhibits a shape with surface regularity which reflects its internal symmetry[Ref1]. The shape of a crystal is often typical of a mineral. and often typical the location where found; thus, crystal shape comprised of. . . Read More

USES OF CLEAVAGE, PARTING, AND FRACTURE IN MINERAL IDENTIFICATION

CLEAVAGE IN A MINERAL CRYSTAL[Ref1] Cleavage in a mineral is the tendency for the crystal to split along definite  crystallographic planes as exemplified by the rhombohedron cleaved from a calcite crystal shown in Figure 1[Ref1]. These planes of weakness are present within a regular repeating array of atoms and ions within the crystal and are. . . Read More

FRACTURE IN MINERAL IDENTIFICATION

Fracture in mineralogy is the texture and shape of the surface formed when the mineral is fractured. Fracture differs from cleavage and parting, which involve clean splitting along a plane surface, as it produces rough irregular surfaces [Ref1]. The appearance of fracture surfaces among minerals is highly varied and is a useful tool in identification.. . . Read More

USES OF CLEAVAGE, PARTING, AND FRACTURE IN MINERAL IDENTIFICATION-I

Structural failure of a mineral crystal can occur by cleavage, by parting, or by fracture.  The characteristics of any of these failure modes exhibited by a mineral can be useful as tools towards its identification. In this Blog I’ll discuss the properties of cleavage and their use in identifying minerals and follow with a second. . . Read More

GALLERY OF CHINESE CARVED JADE ART

To the great advantage of the beauty of their art, Chinese carvers of jade were guided by themes and decorative motifs in the shaping of their carvings and the choices of decorative motifs adorning them[Ref1-7].  In the Neolithic Era of China ritual jade carvings found in burials reflecting the cosmology of the heavens and the. . . Read More

HISTORY OF JADE CARVING IN CHINA

From the late Neolithic Age (circa 3500 BC-2070 BC) into today the crafting of jade art objects in China has produced beautiful and magnificent art objects which exhibit remarkable diversity of both color and form as shown by the carved nephrite jade pendant with phoenix pattern and the funerary Bi Disc with rain pattern in. . . Read More

MINERAL STUFF: THE GEMSTONE JADE

Since ancient times jade[Ref1] has been used by artisans to create beautiful jewelry and works of art. Art objects of jade have been carved in China for more than 6000 years[Ref2] as exemplified by the jade dragon carved during the Zhou Dynasty (5th – 4th century BC) as shown in Figure 1. In Central America,. . . Read More

PALEONTOLOGY OF AMBER

In this Blog I’ll describe how biomaterials including animal and plant fossils are included and preserved in amber formed from tree resin, which by its stickiness can entrap objects which contact its surface as shown in Figure . With further addition of the resin the object is sealed within the resin and out of the. . . Read More

MINERAL STUFF: AMBER, THE GEM

Amber is a hard resin formed from tree sap by fossilization and is many millions of years old[Ref1]. Since Neolithic times (about 9000-3000 BC) and before the Copper Age[Ref]2) amber has been highly valued as a gemstone and used to create beautiful jewelry and artworks. Wide use of amber in Early Europe and in the. . . Read More