Fluorescent Minerals

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One of the latest phenomena that are being exhibited in museums is fluorescent minerals or in simple terms, rocks that glow. These rocks and stones put on an amazing show for the public and really show off every shade that they are coloured with. This spectacular occasion is created by science and light to encourage people to enjoy the marvel of what nature can create. But what exactly are fluorescent minerals and how does emit a glorious rainbow of so many colours?

What Are Fluorescent Minerals?

Fluorescent minerals are not as wonderfully special as it might seem, but they certainly are unique. All minerals have the ability to reflect light which is why we see them and why they shine. However, some minerals contain a very interesting property called fluorescence. These minerals have the ability to absorb a small amount of light at a time and then temporarily store it. An instant later it is released at a different wavelength. This change in wavelength allows the person who observes it to see different colours inside of the mineral. This colour feast is best observed when the minerals are placed in the dark and they are illuminated by an ultraviolet light. During this process they release visible light.

The key component to making this magic show happen is fluorescence. This occurs when the mineral is illuminated by a specific light with a specific wavelength. The type of wavelengths that usually trigger fluorescence are x-rays, ultraviolet rays (UV), and cathode rays. As soon as these lights are focused on the minerals, they activate susceptible electrons within the mineral’s atomic structure. These activated electrons then jump into a higher orbit within the structure for a small period of time. As soon as they come back down to their original orbit, a small amount of energy is released in the form of light. This release is then known as fluorescence.

The light that is released often has a different wavelength to the source of light under which the mineral was exposed to. This is what produces the change of colour in the mineral. The glow of the rock will continue for as long as the mineral is illuminated by the proper light that emits the proper type of wavelength.

History Of Fluorescent Minerals

The history of the fluorescent mineral is very interesting and dates back to the 19^th century. The first person to observe this phenomenon was George Gabriel Stokes in 1852. He found that fluorite had the ability to produce a blue glow that went way beyond that of violet light found on the colour spectrum. This is where the name ‘fluorescence’ got its name from. Since then the term has become known in a wide range of subjects and disciplines such as biology, optics, minerology, and gemology.

Most minerals do not have a noticeable fluorescent quality to them, which is why these minerals are so unique. There are only about 15% of minerals that contain fluorescent qualities that are visible to the naked eye. Even then some of the minerals in that percentage might not deliver a fluorescence that is easily seen. Fluorescence usually occurs when ‘activators’ are present within the mineral. These activators are specific impurities which typically consist of cations of metals like tungsten, molybdenum, lead, boron, titanium, manganese, and uranium. Rare earth elements have also been known to have fluorescent properties and these include minerals such as europium, terbium and yttrium. Other minerals that might portray fluorescent properties are those that contain impurities within the structure.

Some minerals can also reject an activator if it is not the right sort of metal. Minerals might not be fluorescent if iron or copper are present. These metals totally dampen the effect of fluorescence and can even eliminate the effect completely. If you want to try and experiment with fluorescence on your own, you have to make sure that these metals are kept away from the minerals at all times. It is better to stick to the metals that are listed above for an amazing effect.

Mineral Fluorescence Color

Generally, minerals will only fluorescence in one colour, but there are others that have been known to fluorescence in more than one colour. Calcite, for example, can show off in red, blue, white, pink, green, and orange during fluorescence. Minerals can also show off different colours in one single specimen. These minerals are banded and usually show several stages of growth from parent minerals with different structures and changing compositions. A lot of these minerals can produce different colours under different types of UV light. Under a short-wave UV light it might produce a different colour than when it is placed underneath long-wave UV light.

Many specimens that contain fluorite have a strong fluorescence and it might be possible for the observer to take it outside in the sunlight and then back in the shade to view the colours it produces. Fluorite usually glows a blue colour under a long-wave and short-wave light, but there has been cases where it glowed cream or white. The best method to use for minerals to fluoresce is the use of a UV light and a dark environment. You can also make use of a scientific-grade lamp that is used in mineral studies, but these lamps are not as easy or as affordable to find as a UV light. Whichever light you choose to use, remember to make sure that you are using proper eye protection, and avoid shining the UV light directly onto your skin as this can cause sunburn.

In today’s modern world, these advances of ‘glowing rocks’ can be used for scientific purposes in the fields of mineralogy and even petrology. Geologists can find certain types of oils in stones by letting a small amount of UV light shine in the openings and looking at the light it emits. These little minerals have the ability to lighten up our entire world by just letting their colours shine.

BUY YOUR OWN FLUORESCENT MINERALS

Jedan od najnovijih fenomena koji se izlaže u muzejima su fluorescentni minerali ili jednostavnije rečeno, stijene koje svijetle. Ovo kamenje priredilo je nevjerojatnu predstavu za javnost i doista pokazuju svaku nijansu kojom su obojeni. Ovu spektakularnu prigodu stvorili su znanost i svjetlost kako bi potaknuli ljude da uživaju u čudu onoga što priroda može stvoriti. Ali što su zapravo fluorescentni minerali i kako emitiraju veličanstvenu dugu toliko mnogo boja?

Što su fluorescentni minerali?

Fluorescentni minerali nisu tako čudesno posebni kao što se čini, ali su svakako jedinstveni. Svi minerali imaju sposobnost reflektiranja svjetlosti zbog čega ih vidimo i zašto svijetle. Međutim, neki minerali imaju vrlo zanimljivo svojstvo koje se zove fluorescencija. Ovi minerali imaju sposobnost apsorbirati malu količinu svjetlosti odjednom i zatim je privremeno pohraniti. Trenutak kasnije oslobađa se na drugoj valnoj duljini. Ova promjena valne duljine omogućuje osobi koja je promatra da vidi različite boje unutar minerala. Ovu gozbu boja najbolje je uočiti kada se minerali stave u mrak i obasjaju ultraljubičastim svjetlom. Tijekom tog procesa oslobađaju vidljivu svjetlost.

Ključna komponenta za održavanje ove magične predstave je fluorescencija. To se događa kada se mineral obasja određenim svjetlom određene valne duljine. Vrsta valnih duljina koje obično pokreću fluorescenciju su x-zrake, ultraljubičaste zrake (UV) i katodne zrake. Čim se ta svjetla fokusiraju na minerale, aktiviraju osjetljive elektrone unutar atomske strukture minerala. Ti aktivirani elektroni zatim skaču u višu orbitu unutar strukture na kratko vremensko razdoblje. Čim se vrate u svoju izvornu orbitu, oslobađa se mala količina energije u obliku svjetlosti. Ovo oslobađanje je tada poznato kao fluorescencija.

Svjetlost koja se oslobađa često ima drugačiju valnu duljinu od izvora svjetlosti kojoj je mineral bio izložen. To je ono što uzrokuje promjenu boje u mineralu. Sjaj stijene nastavit će se sve dok je mineral osvijetljen odgovarajućom svjetlošću koja emitira odgovarajuću vrstu valne duljine.

Povijest fluorescentnih minerala

Povijest fluorescentnog minerala vrlo je zanimljiva i seže u ^19. stoljeće. Prva osoba koja je promatrala ovaj fenomen bio je George Gabriel Stokes 1852. godine. On je otkrio da fluorit ima sposobnost stvaranja plavog sjaja koji je daleko veći od ljubičaste svjetlosti koja se nalazi u spektru boja. Otuda naziv 'fluorescencija'. Od tada je pojam postao poznat u širokom rasponu predmeta i disciplina kao što su biologija, optika, mineralologija i gemologija.

Većina minerala nema primjetnu fluorescentnu kvalitetu, što je razlog zašto su ovi minerali toliko jedinstveni. Postoji samo oko 15% minerala koji imaju fluorescentna svojstva koja su vidljiva golim okom. Čak i tada neki od minerala u tom postotku možda neće dati fluorescenciju koja se lako vidi. Fluorescencija se obično događa kada su 'aktivatori' prisutni unutar minerala. Ovi aktivatori su specifične nečistoće koje se obično sastoje od kationa metala poput volframa, molibdena, olova, bora, titana, mangana i urana. Također je poznato da elementi rijetkih zemalja imaju fluorescentna svojstva, a to uključuje minerale kao što su europij, terbij i itrij. Ostali minerali koji bi mogli pokazati fluorescentna svojstva su oni koji sadrže nečistoće unutar strukture.

Neki minerali također mogu odbiti aktivator ako to nije prava vrsta metala. Minerali možda neće biti fluorescentni ako su prisutni željezo ili bakar. Ovi metali potpuno prigušuju učinak fluorescencije i čak ga mogu potpuno eliminirati. Ako želite sami isprobati i eksperimentirati s fluorescencijom, morate se pobrinuti da se ti metali cijelo vrijeme drže podalje od minerala. Za nevjerojatan učinak bolje je držati se metala koji su gore navedeni.

Mineralna fluorescentna boja

Općenito, minerali će fluorescentirati samo u jednoj boji, ali postoje i drugi za koje je poznato da fluorescentiraju u više od jedne boje. Kalcit, na primjer, može se pokazati u crvenoj, plavoj, bijeloj, ružičastoj, zelenoj i narančastoj boji tijekom fluorescencije. Minerali također mogu pokazati različite boje u jednom jedinom primjerku. Ovi minerali su vrpčasti i obično pokazuju nekoliko faza rasta od matičnih minerala s različitim strukturama i promjenjivim sastavima. Mnogi od ovih minerala mogu proizvesti različite boje pod različitim vrstama UV svjetla. Pod kratkovalnim UV svjetlom može proizvesti drugačiju boju nego kad se stavi ispod dugovalnog UV svjetla.

Mnogi uzorci koji sadrže fluorit imaju jaku fluorescenciju i promatrač bi ih mogao iznijeti van na sunčevu svjetlost i zatim vratiti u sjenu kako bi vidio boje koje proizvodi. Fluorit obično svijetli plavom bojom pod dugovalnom i kratkovalnom svjetlošću, no bilo je slučajeva kada je svijetlio krem ili bijelo. Najbolja metoda za fluoresciranje minerala je korištenje UV svjetla i tamnog okruženja. Također možete upotrijebiti znanstvenu lampu koja se koristi u proučavanju minerala, ali te lampe nije tako lako ili pristupačno pronaći kao UV svjetlo. Koje god svjetlo odabrali koristiti, ne zaboravite koristiti odgovarajuću zaštitu za oči i izbjegavajte izravno izlaganje UV svjetla na kožu jer to može uzrokovati opekline.

U današnjem modernom svijetu, ovaj napredak 'sjajećeg kamenja' može se koristiti u znanstvene svrhe u poljima mineralogije, pa čak i petrologije. Geolozi mogu pronaći određene vrste ulja u kamenju tako da puste malu količinu UV svjetla da zasja u otvorima i promatraju svjetlost koju ono emitira. Ovi mali minerali imaju sposobnost posvijetliti cijeli naš svijet samo puštajući da njihove boje zasjaju.