LGC is fortunate in having the backing of its world renowned analytical chemistry section.This means that we can use high end techniques to examine inks such as Matrix Assisted Laser Desorption Ionisation Time of Flight Mass Spectrometry.The warning appeared on page 2 of the n Notwithstanding the gradual decline in the use of cheques, the intercepting of cheques between being filled out and being banked (often while in the mail but sometimes by a person on the inside) is an ongoing problem.A dispute arose as to the genuineness of certain Platinum Certificates purporting to have been issued by the Union Bank of Switzerland.Differentiating inks can be important in cases where a document is suspected of having been altered.A classic example is where a zero is added to a cheque making the value ten times as much.
Inks may also be distinguished by other more complex chemical tests but these are likely to be destructive to some extent.
These two ink aging methods are the Sequential Extraction Technique (SET) and Solvent Loss Ratio Method (SLRM).
The SET and SLRM measure certain ink aging parameters of ink that decrease as ink ages on paper. To date, the SET is the only ink aging method that has shown its reliability through outside proficiency testing using “blind” samples (outside proficiency tests in 1995, 2001, and 2011). Ink Availability Approach The second ink dating approach analyzes the chemical composition of inks on a contested document with the aim to determine whether these inks (as well as other materials used to produce the document – paper, inkjet printing ink, toner, stamp pad ink, etc.) were commercially available on or prior to the date appearing on the document. – The examination’s purpose is to assess whether the entries being compared were produced with the ink of the same composition or with different inks (pens). The order of execution of certain elements of a document Writing ink sequencing – Examining intersections (areas where two or more pen lines cross) to determine the order of writing (it may prove that a particular entry was added at a later time) Sequencing of indented impressions and writings – Examining intersections (areas where the visible ink lines cross the indentations) may determine the order of writing and thus prove that a particular entry was added at a later time.
Other ink entries are not necessary for comparison. Aginsky has developed the SET as a result of many years of research of the ink aging methodology developed and published by Dr. For example, if the questioned document’s date precedes the manufacturing date for the ink used to sign the document, it is established that the document could not have been signed on the date it bears. Such intra-comparisons of inks may reveal that the questioned entries were not written contemporaneously with the other entries in the file (document). – The examination’s purpose is to assess whether the use of various inks on the document(s) fits a pattern that is either consistent with the dates appearing on the document(s) or indicates preparation "at one time" (during a short period of time). Paper folds – It is often possible to determine whether an ink line that intersects a paper fold was written before or after the paper was folded.
Offset marks – When two pieces of paper are pressed together, marks such as writing (and printing) may be transferred from one to another.