Fluorite lego? No, actual crystals directly from Mother Nature

From various locations, in its amazing variety of colors and habits, Fluorite is a fantastic mineral. Let me start from a location I visited for several months, such as Naica, Chihuahua in Northern Mexico whose location is off the "Panamerican Freeway" between Camargo and Delicias. From this mine, fluorite and other beautiful crystals have been collected, and it became world famous for its recently discovered giant gypsum crystals cave. Naica produced unique crystals of fluorite that vary from a very pale pink to almost transparent specimens with pyrite crystals inside, some of these in my private collection. I worked in this mine while I was still in College back in the late 70's, and to tell you the truth, I really enjoyed it, as I was assistant of the most prominent Mineralogist in Mexico Dr Raul Ortiz Asiain, and my passion for minerals was already there.

Also, pictures of fluorite from Pointe Kurz (3600 m altitude), Mont Blanc Massif, Haute-Savoie, France, and finally from Caldera 3, Mina Moscona, Solís, Corvera, Asturias Spain

Fluorite:

Chemical Formula: CaF2
Composition: Molecular Weight = 78.07 gm
Calcium 51.33 % Ca 71.83 % CaO
Fluorine 48.67 % F 48.67 % F
Environment: Low temperature vein deposits
Crystal System: Isometric - HexoctahedralH-M Symbol
Cleavage: {111} Perfect, {111} Perfect, {111} Perfect
Color: White, Yellow, Green, Red, Blue.
Density: 3.01 - 3.25, Average = 3.13
Diaphaneity: Transparent to subtranslucent
Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Habit: Crystalline - Coarse - Occurs as well-formed coarse sized crystals.
Habit: Disseminated - Occurs in small, distinct particles dispersed in matrix.
Habit: Massive - Granular - Common texture observed in granite and other igneous rock.
Hardness: 4 - Fluorite
Luminescence: Fluorescent, Short UV=blue, Long UV=blue.
Luster: Vitreous (Glassy)
Streak: White

Lead vanadate forms Vanadinite, discovered in Mexico

Mine: San Carlos (Mina Apex), San Carlos, Manuel Benavides, Chihuahua Mexico
Pb5(VO4)3Cl

Vanadinite is an uncommon mineral, only occurring as the result of chemical alterations to a pre-existing material. It is therefore known as a secondary mineral. It is found in arid climates and forms by oxidation of primary lead minerals. Vanadinite is especially found in association with the lead sulfide, galena. Other associated minerals include wulfenite, limonite, and barite.[2][4][5]

It was originally discovered in Mexico by the Spanish mineralogist Andrés Manuel del Río in 1801. He called the mineral "brown lead" and asserted that it contained a new element, which he first named pancromium and later, erythronium. However, he was later led to believe that this was not a new element but merely an impure form of chromium. In 1830, Nils Gabriel Sefström discovered a new element, which he named vanadium. It was later revealed that this was identical to the metal discovered earlier by Andrés Manuel del Río. Del Río's "brown lead" was also rediscovered, in 1838 in Zimapan, Hidalgo, Mexico, and was named vanadinite due its high vanadium content. Other names that have since been given to vanadinite are johnstonite and lead vanadate.

Along with carnotite and roscoelite, vanadinite is one of the main industrial ores of the element vanadium, which can be extracted by roasting and smelting. It is occasionally used as a source of lead. A common process for extracting the vanadium begins with the heating of vanadinite with salt (NaCl) or sodium carbonate (Na2CO3) at about 850°C to produce sodium vanadate (NaVO3). This is dissolved in water and then treated with ammonium chloride to give an orange coloured precipitate of ammonium metavanadate. This is then melted to form a crude form of vanadium pentoxide (V2O5). Reduction of vanadium pentoxide with calcium gives pure vanadium.

Sources: WEikipedia and the University of life!

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