In the old days, deter­min­ing an art forgery was most­ly a mat­ter of nar­ra­tive deduc­tion, a la Sher­lock Holmes.

Thi­a­go Piwowar­czyk and Jef­frey Tay­lor, founders of New York Art Foren­sics, employ such tech­niques to estab­lish prove­nance, trac­ing the chain of own­er­ship of any giv­en work back to its orig­i­nal sale by research­ing cat­a­logues, title trans­fers, and cor­re­spon­dence.

But they also bring a num­ber of high tech tools to the table, to fur­ther prove—or in the case of the alleged Jack­son Pol­lock drip paint­ing above, disprove—a work’s authen­tic­i­ty.

In the WIRED video above, these experts, whose pedi­gree includes degrees in Chem­istry, Foren­sic Sci­ence, and Com­par­a­tive His­to­ry, a Visu­al Arts Man­age­ment text­book, and two Frick Col­lec­tion Fel­low­ships, break the sleuthing process down to five crit­i­cal steps:

1. Estab­lish prove­nance

Obso­lete tech­nol­o­gy has a place in the process too, in the form of a high­ly unre­li­able fax, alleged­ly sent in 1997. It pur­ports to be a pho­to­copy of a type­writ­ten let­ter from 1970, writ­ten by a gallery own­er who talked one of the artist’s for­mer girl­friends into part­ing with a num­ber of works after his death.

Unfor­tu­nate­ly for the painting’s cur­rent own­er, Piwowar­czyk and Tay­lor could find no proof that the gallery or its own­er ever exist­ed. The let­ter also botch­es Pollock’s death date and odd­ly, there’s a blank where the sender’s num­ber would nor­mal­ly be.

Due dili­gence reveals noth­ing resem­bling this paint­ing in the cat­a­logue raison­né of Pollock’s work.

2. Close up visu­al analy­sis

This can be accom­plished with tools as sim­ple as the flash­light and plas­tic caliper Tay­lor uses to exam­ine the sta­ple holes found at reg­u­lar inter­vals along the unsigned can­vas’ edges. In the 1940s, artists start­ed grav­i­tat­ing toward sta­ples over tacks as a method for secur­ing their can­vas­es to stretch­er bars, but would Pol­lock have done so? Like­ly not, to hear him tell it:

I hard­ly ever stretch my can­vas before paint­ing. I pre­fer to tack the unstretched can­vas to the hard wall or the floor. I need the resis­tance of a hard sur­face.

Piwowar­czyk and Tay­lor draw on their oth­er sens­es, too, when per­form­ing this in-depth visu­al inspec­tion. A deep sniff reveals that teabags were used to dis­col­or the can­vas, in hope of mak­ing it appear old­er than it is.

3. Pho­tog­ra­phy with a mul­ti­spec­tral imag­ing cam­era 

This camera’s abil­i­ty to see the Ultra-Vio­let spec­trum allows our foren­sic experts to spot restora­tions, under­draw­ing, and pen­ti­men­ti. Here, the cam­era revealed an under­ly­ing paint­ing whose geo­met­ric lay­out is unchar­ac­ter­is­tic of Pol­lock, as well as a sus­pi­cious­ly ama­teur­ish patch job on the back of the can­vas, anoth­er attempt to make the paint­ing appear old­er than it is.

4. Exam­i­na­tion with an X‑ray flu­o­res­cence spec­trom­e­ter

It looks like a cool Star Wars prop, and allows the exam­in­ers to iden­ti­fy ele­ments in the pig­ment. Here, our “Pol­lock” gets a pass. There’s tita­ni­um (as in Tita­ni­um White) in evi­dence, but that’s per­mis­si­ble for any­thing paint­ed from the 30s onward.

5. Mol­e­c­u­lar Imag­ing and Analy­sis by Raman Spec­troscopy

The forg­er might have got­ten away with it if it weren’t for those med­dling kids and their Raman Spec­tro­scope! The minus­cule sam­ples of paint Piwowar­czyk har­vests from the can­vas reveal all sorts of organ­ic debris that have no place in a Pol­lock, such as dry­wall dust and an acrylic that didn’t come into use ‘til the 1960s.

In con­clu­sion, exer­cise cau­tion and con­sult the experts before pur­chas­ing a high val­ue drip paint­ing this hol­i­day sea­son! Accord­ing to Piwowar­czyk, the fakes—over 100 and pre­sum­ably still counting—outstrip the num­ber of drip paint­ings Pol­lock cre­at­ed through­out his life­time.

Relat­ed Con­tent:

How an Art Con­ser­va­tor Com­plete­ly Restores a Dam­aged Paint­ing: A Short, Med­i­ta­tive Doc­u­men­tary

The Art of Restor­ing a 400-Year-Old Paint­ing: A Five-Minute Primer

How a Book Thief Forged a Rare Edi­tion of Galileo’s Sci­en­tif­ic Work, and Almost Pulled it Off

Ayun Hal­l­i­day is an author, illus­tra­tor, the­ater mak­er and Chief Pri­ma­tol­o­gist of the East Vil­lage Inky zine.  Join her in NYC from Decem­ber 6 — 20 for the 10th anniver­sary pro­duc­tion of Greg Kotis’ apoc­a­lyp­tic hol­i­day tale, The Truth About San­ta, and the next month­ly install­ment of her book-based vari­ety show, Necro­mancers of the Pub­lic Domain. Fol­low her @AyunHalliday.