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View Full Version : Ultraviolet fluorescence of wood species- looking for data/chart



Malcolm Schweizer
02-27-2016, 9:45 PM
Good day all,

I read this article and am looking for a more definitive list of wood species and how they fluoresce.
http://www.wood-database.com/wood-articles/fluorescence-a-secret-weapon-in-wood-identification/

This is for a number of reasons. One is to identify the construction materials used in ruins as well as old buildings. Another is just to verify species when I am not certain. Finally, I want to figure out what type of pine my floors are made of. They fluoresce bright purple- like Barney the Dinosaur purple- when the bare wood is exposed to UV.

Thanks in advance.

John K Jordan
02-27-2016, 10:45 PM
I would like to find the same thing. Information seems incomplete but I haven't searched lately. The "Understanding Wood" book by R. Bruce Hoadley has some information but if I remember correctly some of it conflicts with the Wood Database table. If you don't have that book (it plus "Identifying Wood" are really worth getting) I see Google books has the text and chart, check pages 105, 106 and 107:

https://books.google.com/books?id=5HBH2ibu-ZwC&pg=PA106&lpg=PA106&dq=wood+fluorescence&source=bl&ots=cnPNaEqiwh&sig=Rj4AwEdPPVZyIb2U5l5AJtVAgF8&hl=en&sa=X&ved=0ahUKEwiDravww5nLAhXGdh4KHfW_CJ0Q6AEIWjAM

I found this reference but don't know how to find the paper: https://smartech.gatech.edu/handle/1853/7042

What kind of UV light are you using? The wavelength makes a big difference. After buying several 365 nm lights and finding some were lies (closer to 400 nm) and some were junk, I finally found a good pocket light, the EagleTac P200LC2 365 nm.

BTW, are you aware the US Forest Products Lab will ID up to five samples of wood per year for any US citizen at no charge?

JKJ

Malcolm Schweizer
02-28-2016, 12:24 AM
Thank you, John. I do have "Understanding Wood," but the list lacks a lot of the most common woods. The Wood Database reference is sold out- supposed to be available soon. My link has a table that I believe is what is in that book.

The reference paper you found is 189 megabytes, so I will have to let it download as I sleep. Thanks for that. Down at the bottom is a view/open file link, and it opens in a new window, but at 189mb it is going to take a while.

My light is a cheapie from eBay and not the greatest. It says the center bulb is 385nm and the outer ring of 9 bulbs are 450nm. It seems very white to me, but it did cause some of the flecks in my bathroom tile to fluoresce bright orange! Now that I have experimented, I plan to get a good one. EagleTac was on the short list. Thanks for the verification. Nitecore makes a really good one, although pricey. I may get an underwater one so I can play around with it while diving.

I did not know about the US Forrest Products Lab free testing. WOW! That helps- thanks. I am going to send a few samples to them from my house, as well as some mahogany I get locally to finally verify if it is truly Cuban Mahogany.

John K Jordan
02-28-2016, 7:48 AM
US Forrest Products Lab free testing... I am going to send a few samples to them from my house

Note that they do not always identify the exact variation, maybe depending on who is doing the test and the time they take. For example, we sent some wood once that I had identified with the hand lens as Elm. I was hoping for verification and whether it was American Elm, etc. The one-word result they returned was "Elm".

The difference between the cheap UV and the EagleTac was "night and day". The cheaper lights have so much white the fluorescence is often difficult or impossible to see. I did get one cheap light from Amazon that was good but the second order from the same company was junk.

I got UV recommendations for the EagleTac and the NiteCore from the candlepower forum. I didn't buy the NiteCore yet because of the price but maybe some day. I do have another NiteCore white LED light and it reeks of quality.

JKJ