As mentioned in previous entries, forgeries and counterfeiting were the major factors leading to some simple security measures in the INR. In addition advancement in modern technologies implied more and more security features being incorporated (in MG series of notes). A few of these are mentioned below:
Reference picture is at the document on recent trend of forgeries.
- Paper: Made from 100% cotton. Although, the paper of most of the internationally counterfeited note is also made from the cotton pulp but the gramage of paper is more in these notes and they are thicker in feel. The notes printed on the paper made from wood pulp can be identified by the perception of touch and its crackle sound.
- Watermark: Perhaps the most easily observable feature, the Mahatma Gandhi watermark will be visible with a light and shade effect and multi-directional lines are visible within the watermark window. In some of the counterfeit notes, watermark of Mahatma Gandhi portrait is prepared by the use of hot molded cylinder, with hot wax or white paint/correctional fluid, which can be identified under transmitted or ultra violet light.
- Security Thread: Windowed security thread with visible features and inscription Bharat (in Hindi), and RBI. When held against the light, the security thread on Rs.1000, Rs.500 and Rs.100 can be seen as one continuous line. The security thread appears to the left of the Mahatma’s portrait. Notes issued prior to the introduction of the Mahatma Gandhi Series have a plain, non-readable fully embedded security thread with six shining segments (could be more in a counterfeit one). In the genuine notes, the security thread can be seen as a regular and complete line under transmitted light. Whereas in most of the forged notes this line is visible as a broken or segmented line when held under transmitted light. In the genuine notes, the segmented security thread gives deep blue fluorescence under Ultra Violet light, whereas in the forged notes the security thread give violet or dark or no fluorescence. In some of the notes blue and violet fluorescence can be seen alternatively.
- Latent Image: Hold your note such that the shorter side near MG image on the obverse side is at your eye level. You should be able to spot a vertical band showing the respective denominational value in numeral. In forged notes, this Latent Image is absent
- Micro lettering: Note the line like pattern near MG’s ears on the obverse side of the note. Now try to zoom in on them. You should be seeing the word RBI and denominational value (in case of high value notes) of the notes in micro-letters. It is interesting to note that the forged notes prepared by scanning and colored Xeroxing show only dots or dashes at this area instead of micro printing.
- Intaglio Printing: The portrait of Mahatma Gandhi, the Reserve Bank seal, guarantee and promise clause, Ashoka Pillar Emblem on the left (this one can be very easily felt), RBI Governor’s signature are printed in intaglio i.e. in raised prints, which can be felt by rubbing the obverse side of the note with finger.
- Identification Mark: Ever cared to note how visually impaired recognize notes? If not know it now. Do you see a geometrical shape above the Ashoka Pillar Emblem on obverse side of the note (left most)? This is different for different notes and can be felt by touch. A point to note is that in genuine currency notes the mark will cross the brown vertical near it, something that many counterfeiters might miss out.
- Rs. 20 – Vertical Rectangle
- Rs.50 – Square
- Rs.100 – Triangle
- Rs.500 – Circle
- Rs.1000 – Diamond
- Fluorescence: This is an interesting one and is certainly not for casual observation. Number panels of the notes (top right in obverse side) are printed in fluorescent ink. The notes also have optical fibers mostly yellow, blue or green that is mixed in the pulp at the paper manufacturing stage. Number panels, optic fibers and security thread can be seen with this special feature when the notes are exposed to ultra-violet lamp. In counterfeit notes, there may be fibers of single color (mostly blue) or they are absent. In some of the internationally forged currency notes all these three color fibers are present. Also genuine notes give no fluorescence when exposed to UV light whereas forged ones would mostly give a blue light.
- Optically Variable Ink (OVI): This is a new security feature incorporated in the Rs.1000 and Rs.500 notes with revised color scheme introduced in November 2000. The numeral 1000 and 500 on the obverse of Rs.1000 and Rs.500 notes respectively is printed in optically variable ink viz., a color-shifting ink. The color of the numeral 1000/500 appears green when the note is held flat but would change to blue when the note is held at an angle. In internationally forged notes, the OVI feature is also visible but it is comparatively lighter shade due to screen-printing. In other category of scanned or colored Xeroxed notes, this feature is very absent.
- See through Register: The small floral design (above id mark as mentioned above) printed both on the front (hollow) and back (filled up) of the note in the middle of the vertical band next to the Watermark (left most in front, right most in back) has an accurate back to back registration. In some cases, the design will appear as one floral design, indicating the currency value, when seen against the light. In the counterfeit notes, the petals of brown flower do not align with white flower (on other side) and they look comparatively darker in color.
- A couple of other features worth mentioning are the stripe patterns that are visible in the notes (when observed closely). They’re like finger prints for each denomination unique!
- Also some of the newer notes include the EURion Constellation (five small rings on top). It is added to help software detect the presence of a banknote in a digital image. Such software can then block the user from reproducing banknotes to prevent counterfeiting using color photocopiers. The mere presence of five of these circles on a page is sufficient for some color photocopiers to refuse processing!
- Other techniques used to prevent forgery include:
- Font Size: Comparison of numbers and series show differences in font size.
- Ink Jet Printing: Genuine notes are printed with offset and Intaglio printing having continuous and sharp lines, something not so attainable with the common Ink Jet printers used for counterfeiting.
- Xerox Copy Notes: The counterfeit notes prepared by multi colored Xerox copying technique show sheen (shining surface) of printing on both side of the notes developed due to thermal effect of Xeroxing technology. The notes having sheen on the printed design will lack paper and printing security features.
- RBI check: In the genuine notes the printing of this emblem shows sharp printing with district and clear-cut lines. Whereas, in the counterfeit notes printing of emblem is poor and with smudged lines. Further, in genuine note there is a distinct dot below the letter Ja of the Hindi word Reserve, in the forged notes this dot is missing.
I believe the above mentioned points are but few of the well known security features. Knowing the mindset of the quacks I guess it would be ill advised if RBI went around publishing all of its protective designs.
Every single dot and line in the note that we so casually carry has so much information within it. I hope the next time you make a transaction know your money’s worth and you’ll know (at least) partly the efforts and thoughts that have gone into designing that piece of paper.