Does Monazite fluoresce under UV light?

[laserboy99]

I know there have been a few posts about minerals that fluoresce when 280nm light is shown on them. But, does anyone know specifically if the thorium within monazite fluoresces when a 280nm laser or say a 300lumen UV flashlight is pointed at it? I could just go out to the field and start looking around but I thought I'd take the more experienced route first. To qualify this question, I'm looking to collect thorium samples to test their neutron emissions. It'd be great if I could just hop on over to Idaho during the night, fire up the UV torch, and look at a field of pink or purple sparkles staring right back at me. Any feedback would be great, or even book resources.

Thanks!
- damon

 

[CurtisOliver]

I found this.

As for having a laser in the region of 280nm. Not unless you have a lot of spare cash lying around. UV lasers are rare and cost a fortune.

 

[laserboy99]

SWEET! Curtis this is awesome. I'll check over the link later this afternoon. Thank you!!

 

[paul1598419]

I was a rock hound back in the early 1960s and had several fluorescent rocks and minerals back then. I passed my collection onto my daughter many years ago, but still have a calcite slab that splits images on paper depending on the polarity of the calcite.

 

[CurtisOliver]

I was a rock hound back in the early 1960s and had several fluorescent rocks and minerals back then. I passed my collection onto my daughter many years ago, but still have a calcite slab that splits images on paper depending on the polarity of the calcite.

I have some optical calcite too. The birefringence is a cool affect with lasers.
My sister like crystals, but whenever we go to a crystal stall I try to pick up any crystal that shows some optical feature. My sister’s collection is quite extensive unlike my own. She likes them for the general appearance.

Funny enough that we’re on this subject as I picked up another piece of fluorite and some Baltic amber today. I also got some koroit boulder opal and sulphur quartz too.

These are the crystals I have:

Tourmaline
Citrine
Labradorite
Clear Quartz
Yellow Quartz
Calcite
Optical Calcite
Blue Cats Eye Quartz
Uranium Glass
Uranium Glass (Art Deco)
Karoit Boulder Opal
Sulphur Quartz
Baltic Amber
Ruby (Laser rod)
Fluorite (Green) x2
Fluorite (Blue)
Jade
Emerald
Rose Quartz
Amethyst
Lapis Lazuli

Calcite is a good one. It glows bright pink. But it also is phosphorescent.

Despite the name, it’s not as common to get fluorescing fluorite as you imagine. The first sample has either very weak emission or the fluorescence is an illusion.

The new one is of a higher proportion of green fluorite crystals so I’m hoping for more luck getting it to fluoresce blue.

 

[paul1598419]

I had a large Fluorite crystal in my collection over two inches in diameter and a deep violet color. I had garnets, many quartz crystals and several I can't even remember any longer. Unfortunately, my daughter can't find the collection as she has moved several times in the past 20 years. ;(

 

[CurtisOliver]

That is a shame. Quartz seems to be one of the most common crystals to get.

 

[paul1598419]

Yeah, it depends on the crystal size and color for quartz. I had several amethyst examples from Brazil, but the best amethyst are a deep purple color and come from Russia and places in Europe. I got some blue quartz that I found in the Blue Ridge mountains which is the best place to find that in the US according to my rock and mineral books.

 

[CurtisOliver]

Gems are quite rare to come across in the uk now by an amateur. I did find though that Amber can be found on the east coast.

Quartz seems to be mainly from Scotland.
I nearly picked up some rose quartz the other day too. But how many varieties of quartz do I need.

 

[paul1598419]

I had a large piece of rose quartz in my collection about half the size of my fist. It was a present that my parents gave me many years ago. I didn't ever learn exactly where it came from.

 

[CurtisOliver]

I had a large piece of rose quartz in my collection about half the size of my fist. It was a present that my parents gave me many years ago. I didn't ever learn exactly where it came from.

South Dakota was quite a big source years back. Could have been from there. Otherwise there are far too many locations to narrow it down to.

 

[steve001]

I've a class 3b 405nm laser. I have found many things that fluorese under that wavelength. Even found some rocks that are phosphorescent or thermoluminesent. They glow orange. Even old white paint glows a pale bluish white. Old cement same color as the paint.

 

[CurtisOliver]

I've a class 3b 405nm laser. I have found many things that fluorese under that wavelength. Even found some rocks that are phosphorescent or thermoluminesent. They glow orange. Even old white paint glows a pale bluish white. Old cement same color as the paint.

Same here. In fact that’s my main source of fluorescing light.
I do also have a multi watt UV LED that needs heatsinking.

I went to a vintage fair today. Picked up a piece of art deco uranium glass.

 

[laserboy99]

I had a chemistry class where the teacher was a collector of phosphorescent stones. One of the stones, it may have been quartz, fluoresced with a beautiful red color.

 

[laserboy99]

View attachment 75054
I found this.

As for having a laser in the region of 280nm. Not unless you have a lot of spare cash lying around. UV lasers are rare and cost a fortune.

As for having a laser in the region of 280nm. Not unless you have a lot of spare cash lying around. UV lasers are rare and cost a fortune.

I tried checking out www njminerals org/FO200104 HTM and it says the page is not found. Suggestions?

 

[CurtisOliver]

Luminescence, fluorescence and phosphorescence of minerals

Database of luminescent (fluorescent) minerals including emission spectra and activators

www.fluomin.org

Uranium dioxide is the most common fluorescent in monazite, thorium itself I haven't found evidence for a fluorescent marker. However the decay chain of uranium produces some thorium. So if uranium dioxide is present it may indicate a healthy quantity or uranium and therefore a decay chain. However this is still no guarantee.