ClipArt ETC
Calcite Crystal; This is one particular habit of a calcite (Calcium Carbonate) crystal.

Calcite

Calcite Crystal; This is one particular habit of a calcite (Calcium Carbonate) crystal.

Calcite Crystal; This is one particular habit of a calcite (Calcium Carbonate) crystal.

Calcite

Calcite Crystal; This is one particular habit of a calcite (Calcium Carbonate) crystal.

This figure shows the combination of forms on calcium hyposulphite (CaS_2_O_3_ + 6 aq). If we assume the face c as the basal pinacoid, and b as the brachypinacoid, then the symbols of the other planes become: (p), (p'), and (q).

Calcium Hyposulphite

This figure shows the combination of forms on calcium hyposulphite (CaS_2_O_3_ + 6 aq). If we assume…

This crystal of Calcium Phosphate, Apatite, represents a complex combination of hexagonal hemihedral forms produced by the pyramidal selection. The nine forms comprise the basal pinacoid ,(P); the prism of the first order, (M); second order, (u); and third order, (h); three pyramids of the first order, (r), (x), and (y); one pyramid of the second order, (s); and one of the third order, (m).

Calcium Phosphate, Apatite

This crystal of Calcium Phosphate, Apatite, represents a complex combination of hexagonal hemihedral…

Also known as Diopside, this crystal exhibits symbols whose forms are: (c), (b), (a), (m), (o), and (u).

Calcium-Magnesium Metasilicate

Also known as Diopside, this crystal exhibits symbols whose forms are: (c), (b), (a), (m), (o), and…

This candelabrum is formed of the purest crystal. It can hold fifteen lights.

Candelabrum

This candelabrum is formed of the purest crystal. It can hold fifteen lights.

Cassiterite.

Cassiterite

Cassiterite.

"Tetragonal. Common forms are prisms and pyramids of first and second orders." — Ford, 1912

Cassiterite

"Tetragonal. Common forms are prisms and pyramids of first and second orders." — Ford, 1912

Cassiterite is a tin oxide mineral, SnO<sub>2</sub>. It is generally opaque but is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite is the chief ore of tin today.

Cassiterite

Cassiterite is a tin oxide mineral, SnO2. It is generally opaque but is translucent in thin crystals.…

Cassiterite is a tin oxide mineral, SnO<sub>2</sub>. It is generally opaque but is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite is the chief ore of tin today.

Cassiterite

Cassiterite is a tin oxide mineral, SnO2. It is generally opaque but is translucent in thin crystals.…

Cassiterite is a tin oxide mineral, SnO<small><sub>2</sub></small>. It is generally opaque but is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite is the chief ore of tin today.

Cassiterite

Cassiterite is a tin oxide mineral, SnO2. It is generally opaque but is translucent in thin crystals.…

Celestite.

Celestite

Celestite.

"Orthorhombic. Crystals resemble closely those of barite. Commonly tabular parallel to the base or prismatic parallel to the brachy- or macro-axis with prominent development of the domes. Crystals which are elongated parallel to the brachy-axis are frequently terminated in front by four faces in nearly equal development, consisting of 2 prism faces and 2 of the macrodome." &mdash; Ford, 1912

Celestite

"Orthorhombic. Crystals resemble closely those of barite. Commonly tabular parallel to the base or prismatic…

"A crystal has a center of symmetry if an imaginary line is passed from some point on its surface through its center, and a similar point is found on the line at an equal distance beyond the center." &mdash; Ford, 1912

Symmetry center

"A crystal has a center of symmetry if an imaginary line is passed from some point on its surface through…

"Habit varied and crystal show many forms. Crystals often tabular parallel to brachypinacoid." &mdash; Ford, 1912

Cerussite

"Habit varied and crystal show many forms. Crystals often tabular parallel to brachypinacoid." —…

In the orthorhombic system, tabular crystals of lead carbonite (cerussite), bounded by the forms ∞P∞̆, {010} (b); ∞P, {110} (m); and P, {111} (p), form groups in which both (m) and ∞P3̆, {130} act as twinning planes.

Cerussite

In the orthorhombic system, tabular crystals of lead carbonite (cerussite), bounded by the forms ∞P∞̆,…

Chabazite.

Chabazite

Chabazite.

"Hexagonal-rhombohedral. Common form is the simple rhombohedron, r, having nearly cubic angles. May show several different rhombohedrons." &mdash; Ford, 1912

Chabazite

"Hexagonal-rhombohedral. Common form is the simple rhombohedron, r, having nearly cubic angles. May…

Chalcanthite.

Chalcanthite

Chalcanthite.

"Orthorhombic. Usually in small tabular crystals with hexagonal outline. Striated parallel to the brachy-axis. Often twinned in pseudohexagonal forms." &mdash; Ford, 1912

Chalcocite

"Orthorhombic. Usually in small tabular crystals with hexagonal outline. Striated parallel to the brachy-axis.…

The Copper Sulphide, Chalcocite, forms three kinds of twins symmetrical to ∞P, {110}, to 4/3P∞&#774;, {043}, and to 1/2P, {112} respectively. The latter is shown in this figure.

Chalcocite

The Copper Sulphide, Chalcocite, forms three kinds of twins symmetrical to ∞P, {110}, to 4/3P∞̆,…

"A drawing of a crystal showing a combination of the cube, octahedron and rhombic dodecahedron is shown, in which the faces are lettered the same as the corresponding poles in the projection." -The Encyclopedia Britannica 1910

Clinographic Drawing of a Cubic Crystal

"A drawing of a crystal showing a combination of the cube, octahedron and rhombic dodecahedron is shown,…

"Orthohombic. Habit of crystals is short prismatic; often in square prisms because of prominent development of the vertical pinacoids. Terminated by basal plane, pyramids and domes; frequently complex." &mdash; Ford, 1912

Columbite

"Orthohombic. Habit of crystals is short prismatic; often in square prisms because of prominent development…

"The combination of hexakis-octahedron and cube.

Combination of Hexakis-octahedron and Cube

"The combination of hexakis-octahedron and cube.

The combination of icositetrahedron and rhombic dodecahedron.

Combination of Icositetrahedron and Rhombic Dodecahedron

The combination of icositetrahedron and rhombic dodecahedron.

The combination of an icositetrahedron and a cube.

Combination of Icositetrahedron and Cube

The combination of an icositetrahedron and a cube.

The combination of an icositetrahedron and an octahedron.

Combination of Icosietetrahedron and Octahedron

The combination of an icositetrahedron and an octahedron.

Represents the combination of pentagonal dodcahedron, dyakis-dodecahedron and octahedron.

Combination of Pentagonal Dodecahedron, Dyakis-dodecahedron, and Octahedron

Represents the combination of pentagonal dodcahedron, dyakis-dodecahedron and octahedron.

"...shows the rhombic dodecahedron in combination with the octahedron." -The Encyclopedia Britannica 1910

Combination of Rhombic Dodecahedron and Octahedron

"...shows the rhombic dodecahedron in combination with the octahedron." -The Encyclopedia Britannica…

A tetrahedral combination.

Combination of Tetrahedron, Cube and Rhombic Dodecahedron

A tetrahedral combination.

The combination of tetrakis-hexahedron and cube.

Combination of Tetrakis-hexahedron and Cube

The combination of tetrakis-hexahedron and cube.

The combination of a cube and a triakis-octahedron.

Combination of Triakis-octahedron and cube

The combination of a cube and a triakis-octahedron.

"...a combination of these two tetrahedra, and represents a crystal of blende, in which the four larger faces are dull and striated, whilst the four smaller are bright and smooth." -The Encyclopedia Britannica 1910

Combination of two Tetrahedra

"...a combination of these two tetrahedra, and represents a crystal of blende, in which the four larger…

Represents one way a tetrahedron and a cube might combine.

Combination of Tetrahedron and Cube

Represents one way a tetrahedron and a cube might combine.

This figure shows a contact twin of copper, one of the three simplest isometric holohedrons according to the "spinel law".

Copper Contact Twin

This figure shows a contact twin of copper, one of the three simplest isometric holohedrons according…

This is a crystal of Copper Silicate (Dioptase) with a rhombohedron of the third order, (s), in combination with the prism of the second order, (m), and the negative rhombohedron, (r). This crystal is an example of rhombohedral tetartohedrism in the hexagonal system.

Copper Silicate Showing Rhombohedral Tetartohedrism In the Hexagonal System

This is a crystal of Copper Silicate (Dioptase) with a rhombohedron of the third order, (s), in combination…

Corundum.

Corundum

Corundum.

Corundum.

Corundum

Corundum.

"Hexagonal-rhombohedral. Crystals usually prismatic in habit or tapering hexagonal pyramids." &mdash; Ford, 1912

Corundum

"Hexagonal-rhombohedral. Crystals usually prismatic in habit or tapering hexagonal pyramids." —…

"Hexagonal-rhombohedral. Crystals usually prismatic in habit or tapering hexagonal pyramids." &mdash; Ford, 1912

Corundum

"Hexagonal-rhombohedral. Crystals usually prismatic in habit or tapering hexagonal pyramids." —…

A crystal cross set in enameled gold created by a German craftsman in the 16th century.

Cross

A crystal cross set in enameled gold created by a German craftsman in the 16th century.

An illustration of a crystal showing triangular markings.

Crystal

An illustration of a crystal showing triangular markings.

Natural Crystal. 1, Fluorite.

Crystal

Natural Crystal. 1, Fluorite.

A Crystal Aggregate is a union of two or more crystal individuals.

Crystal Aggregate

A Crystal Aggregate is a union of two or more crystal individuals.

"...represents a crystal of augite bounded by th clino-pinacoid, the ortho-pinacoid, a prism, and a hemi-pyramid." -The Encyclopedia Britannica 1910

Crystal of Augite

"...represents a crystal of augite bounded by th clino-pinacoid, the ortho-pinacoid, a prism, and a…

"Here there is only a [center] of symmetry. All the forms are pina-coids, each consisting of only two paarallel faces." -The Encyclopedia Britannica 1910

Crystal of Axinite

"Here there is only a [center] of symmetry. All the forms are pina-coids, each consisting of only two…

"...a combination of two bisphenoids (P and P'), two bipyramids of the second order (b and c), and the basal pinacoid (a)." -The Encyclopedia Britannica 1910

Crystal of Chalcopyrite

"...a combination of two bisphenoids (P and P'), two bipyramids of the second order (b and c), and the…

"...represents a crystal of dioptase with the fundamental rhombohedron (r) and the hexagonal prism of the second order (m) combined with the rhombohedron (s)." -The Encyclopedia Britannica 1910

Crystal of Dioptase

"...represents a crystal of dioptase with the fundamental rhombohedron (r) and the hexagonal prism of…

"...a combination of tetragonal prism of the first order with a tetragonal bipyramid of the third order and the basal pinacoid." -The Encyclopedia Britannica 1910

Crystal of Fergusonite

"...a combination of tetragonal prism of the first order with a tetragonal bipyramid of the third order…

"...a combination of the brachy-pinacoid and a prism, with the pedion, two brachy-domes and two marco-domes at the upper end, and a pyramid at the lower end." -The Encyclopedia Britannica 1910

Crystal of Hemmorphite

"...a combination of the brachy-pinacoid and a prism, with the pedion, two brachy-domes and two marco-domes…

Holohedral orthorhombic combination

Crystal of Hypersthene

Holohedral orthorhombic combination

"...represents a crystal of tourmaline wit the trigonal prism, hexagonal prism, and a trigonal pyramid at each end." -The Encyclopedia Britannica 1910

Crystal of Tourmaline

"...represents a crystal of tourmaline wit the trigonal prism, hexagonal prism, and a trigonal pyramid…

"...shows the actual shape of a crystal of ziron from Ceylon" -The Encyclopedia Britannica 1910

Crystal of Zircon (actual)

"...shows the actual shape of a crystal of ziron from Ceylon" -The Encyclopedia Britannica 1910

"...the ideally developed form [of a zircon crystal]. The crystal is a combination of five simple forms: two tetragonal prisms, two tetragonal bipyramids, and one ditetragonal bipyramid." -The Encyclopedia Britannica 1910

Crystal of Zircon (ideal)

"...the ideally developed form [of a zircon crystal]. The crystal is a combination of five simple forms:…

A beryl crystal, an example of a basal pinacoid.

Beryl crystal

A beryl crystal, an example of a basal pinacoid.

A beryl crystal, an example of a basal pinacoid.

Beryl crystal

A beryl crystal, an example of a basal pinacoid.

A beryl crystal, an example of a basal pinacoid.

Beryl crystal

A beryl crystal, an example of a basal pinacoid.

A beryl crystal, an example of a basal pinacoid.

Beryl crystal

A beryl crystal, an example of a basal pinacoid.

"The forms present upon it are two pyramids of different slope but each intersecting all three of the crystal axes when properly extended. The lower pyramid intersects the two horizontal axes at distances which are proportional to their unit lengths and if it was extended as shown by the dotted lines would also cut the vertical axis at a distance proportional to its unit length." &mdash; Ford, 1912

Sulphur crystal

"The forms present upon it are two pyramids of different slope but each intersecting all three of the…

A Crystalline Aggregate is mass of crystal grains, devoid of their characteristic forms and closely packed together.

Crystalline Aggregate

A Crystalline Aggregate is mass of crystal grains, devoid of their characteristic forms and closely…