This type of paper is considered to be the cream of marked cards. Those who wish to learn the secret of juice have to be willing to pay a handsome amount of money just to get the right information. I know of a source that currently (2004) sells the ready mixed liquid for $200, or you can buy the entire secret for $1,500. I have also heard of cases where the price tag reached two thousand US dollars. However, being willing to pay doesn't do one any good if one can't find a person who, a) knows the real secret, and b) is willing to sell it. Since juice is considered to be the finest marking method known, its secret is reputedly only being sold or passed on to those who are already "in the know".

However, in recent years there has been a lot of junk information, about juice, circulated around the internet. Many half-smarts tried to come up with formulas and cook up something (literally) in their own kitchens. Once they came up with some solutions that they thought would work (meaning that they would be able to sell to the unknowing public) they started listing juice decks, and juice solutions on eBay and various junk web sites. It should be noted that those individuals have absolutely no connections to the gambling world and never had any way to obtain any accurate information. But, as a result of their internet sales, they've managed to misinform the public, world wide.

To the best of my knowledge the secret of juice has never been fully revealed in print although it has been mentioned in several books. It took me several years of persistent research to find out how it works. One of the problems was that no one was able to let me look at a juice deck, so I had no way of drawing any conclusions. I had my own theories but it was impossible to check them against a genuine juice deck since I couldn't get a hold of one at the time. Unlike other card-marking methods, no detailed theory of juice work has yet been released to the public.

In the next few lines you will be able to get a good understanding of how juice works. It should be noted, however, that viewing juice marks requires a great deal of training; some juice decks are made so well that even experts can not see the marks, not even when they are told the marks are in fact there.

juice work: juice deck code

The illustration above represents an old gambler's marking code that has supposedly often been used on juice decks. Note that this deck is probably marked for Blackjack. All the picture cards are marked as tens and the suits are irrelevant. There is no rule to how the cards have to me marked. As with any other marking method many cheats prefer to have their own personal codes. As you can see the marks are large and easy to see, even from a distance ... if ... you know what to look for. How could you miss them? This is precisely the beauty of juice work. You have to train your eyes to be able to see the marks.

Juice patterns are not limited only to the dime-size dots and thick lines shown above. Below are two examples of other coding patterns.

juice work: line juice code
juice work: edge juice code

The pattern on the top is called line juice. In this particular example, the positions of the lines are based on the old classic cheater's code previously described. The lines themselves are quite thin and are capable of blending into a Bee design far better than the large dots of the classic system.

The bottom row shows what I've named edge juice. To the best of my knowledge this code is my own invention that I've developed in the attempt to better hide the patterns. This juice is a lot more difficult to see than the classic code. Even if someone well-informed happens to be looking for juice, they may miss this because the edge work may appear more like shadows (which would not be the case if a savvy person manages to discover the classic code). In any event, if the cards are juiced correctly, nothing should be seen by anyone who doesn't know the proper viewing technique.

I had once had a client who wanted to have several juice deck made to order. He wanted to have all the cards marked for value, as well as for suit. At first I had told him it would be unwise to put additional lines (to represent suits) on the cards, because as a rule of thumb one should minimize the amount of marks - even if is very unlikely anyone would discover the work. However, his persistence led me to develop a system that would not require any additional lines for suits, but would still be able to distinguish the cards from being black-suited or red-suited, which is an added advantage in some games, such as poker.

marked cards: line juice code

The code shown above is called "Juice Code L-26" (my own terminology). The "L" stands for "Line" and the "26" means that the code consists of 26 symbols. This code reveals more information without adding any extra lines (with the exception of the red-suited 2s and 3s). As can be seen from the illustration, the red-suited cards can be distinguished from the black ones simply by the positions of the lines. It should be noted, however, that the code shown above is an old one. I have later developed a slightly different 13-way combination code, with a different 26-way combination code to match.

Now that we've covered some marking codes, let's talk about the actual work.


juice deckTo an untrained eye nothing seems to be out of order with the cards, but to a trained eye these marks are reputedly said to "stand out like neon signs". At least this is what the legend says. This statement is to be taken with a little bit of a poetic licensing, but the fact is that to the paper player these marks are visible from across the table, which is why some cheats have been known to also call juice cards distant readers.

The image at the right is a picture of an actual juice card. This is also how the card would appear to an untrained eye. I never expected juice marks to reproduce on screen and I didn't put it there to show the marks. I just wanted to be absolutely sure everybody understands what kind of cards must be used in order for juice to work. It is absolutely essential to use cards with an even, repeating pattern such as the Bee brand shown on the photo.

The fluid used to mark cards is applied to the backs so that it doesn't leave any apparent stains. However it does leave a residue. This residue effects the way light reflects from the backs of the marked card. When a cheat "turns on his X-ray vision" the areas marked with juice will jump out. A well-trained eye can read juice marks as if the cards were face-up.

Below is a simulation that will help you get a better understanding how to read juice work.


juice cardjuice workThe image to the left is a computer simulation of the way a juiced ace would look like, when properly viewed. Being able to see juice marks is kind of like being able to ride a bicycle. Once you learn how to, it becomes second nature. In the next paragraph I will describe the correct viewing technique. As with any other great trick the secret behind juice is very simple and once you find out how it works it may even be somewhat disappointing. Skeptics may not even be convinced that this is all there is to it.

In order to see juice marks you have to allow your eyes to go out of focus. That's it! When you do this correctly the work will look like shadowy, fuzzy impressions (so, not quite like "neon signs"). Since you do not have a juice card to try it out I simulated the way a juice card would look if you were defocusing your eyes correctly. Oddly enough, if you try to blur your vision while looking at the simulated card on the left, you will further amplify the intensity of the marks and as a result the two dots will look more apparent. If you try to do that, the image you will see will look almost like the picture on the right. So, the juice marks become darker, while the surrounding area becomes lighter. The viewing technique that enhances the simulated marks on this screen is the same viewing technique that brings out the invisible juice marks on actual cards. 

It is very important to defocus your eyes correctly. There are two ways in which you can achieve a blurred vision, and only one way is the correct way. The way it should be done is by defocusing your eyes. If you do it right you should see a single image out of focus. If you are having a hard time achieving this you should try squinting. Squinting is not the correct way to view juice (obviously) but it helps break the ice. In fact if you try squinting at the simulated juice card on the left the marks will, once again, become more visible.

To better understand the correct viewing technique, it is a good idea to have a good understanding of the incorrect technique. So that you know what not to do.


viewing juice marksThe incorrect way to blur your vision is also the most common mistake people make when they first attempt the viewing exercise. That would be by either crossing your eyes or by diverging them. As a result you would see a double image. If you were looking at a Bicycle brand card in this manner you would see an image resembling the photo to the right. The image is not really out of focus; you actually see two images that are not in proper alignment. In fact, you would not be blurring your eyes at all, you would just be forcing each eye to look at a different focal point on the card. The reason why I used a Bicycle card for this particular simulation is because, unlike a Bee card, it does not have a repeating pattern. If I were to show you an off-set double exposure of a Bee card it could look perfectly in focus because two identical parts of the repeating pattern may fall in alignment. 

The viewing technique is only half of the secret. The big secret is the juice recipe. There are a few different substances that can be used. An old recipe was passed on to me by a friend. It is a mixture of a solvent and another product which you can no longer find on the market (which is the reason why I am willing to give away this particular juice recipe). The brand name of that particular product used to be Octibrite®. This used to be a detergent additive used to make white clothes shine bright in the sun. When applied correctly it would be totally invisible if you did not know how to look at the cards, however to a trained eye the marks would really stand out.

However, Octibrite® is not really the ingredient for juice. It is only one variation because this substance produced good results. I assume that Octibrite® used to contain some of the actual chemical that was originally used for juice. This original chemical is luckily still available on the market, if you know what it is. Later another chemical was discovered to work equally well (for some cards even better) and a juice recipe was produced that uses a mix of both chemicals in 1:1 ratio.

Finally, even knowing the exact juice recipe won't do you any good, if you do not know the proper application technique. This is a fact that is greatly ignored by all the merchants that are supposedly selling juice. In fact, the biggest secret is not really the recipe itself, it is in fact the application technique. I like to use an analogy, when explaining this fact. If someone gave you the exact same paints and paintbrushes that Leonardo da Vinci was using, would you be able to paint the Mona Lisa? To make up a juice deck, you require talent and experience.


This chapter would not be complete without explaining how to detect juice work. Since the substance used to mark the cards is a liquid it may leave an impression on the backs, if applied incorrectly, or if the wrong painting technique is used. If you take a drop of water and rub it in with a Q-tip® onto the back of a card it will leave the same impression as juice would, if it had been applied incorrectly. By this I mean if you let the card dry and look at it against light, so all you see is the light being reflected off of the surface, you will be able to see a slight dimple where the card was wet. The card is slightly embossed as a result of expansion, as the paper was absorbing the liquid. The depth of that buckle is so minute that it is easily missed and it may even wear out as the cards get used. But it may be there, and if it is, it's evidence.

juice card: black light testAnother way to inspect juice cards is to look at them under a black lamp - this is an ultra violet lamp that produces light waves in the range of 365nm to 254nm, depending on the bulb used. Black lights are also used to detect forgeries and art restorations. Depending on the recipe, some juice work may show up under a black light and may really shine like "neon signs." The image shows a computer simulation of a juice card tested under a black light. Under black illumination the un-printed areas of white would look dark purple, while the juiced areas of exposed white paper would fluoresce as bright purple. Again, only the un-printed blank areas of the card would fluoresce; the printed ares may just lighten up a tad but would not look fluorescent.

It should be noted, however, that the black-light test does not work on all brands of playing cards because some playing card makers use paper stock that already fluoresces. Therefore the same juice work that fluoresces on a Bee card would be undetectable on a Gemback, under black illumination, because Gemaco Playing Cards uses paper that already fluoresces. In other words, if you place a Bee card and a Gemback side-by-side under a black lamp, the Bee will look dark and the Gemback will shine like a neon sign. Again, only the exposed blank paper of the Gemback will fluoresce - not the printed back design.

Although this marking method is quite ingenious I still don't think that it is the best way to mark cards. The evidence is still on the cards and there is a possibility that it gets discovered (and it often does) - even if by accident. Some people may absentmindedly defocus while staring blankly at the cards and notice something. Oddly enough if anyone is shortsighted, and they take their glasses off, they may notice the marks simply because their eyes can't focus at a distance. As far as I am concerned, there goes the perfect marking system down the drain.


I can imagine that some of you may be eager to look at an actual juice card just to see if you can see the marks. Luckily you can perform a simple eye test which comes close to looking at an actual juice card. Just take a Q-tip® and rub a small amount water onto the back of a Bee card (blue or red - it doesn't matter). Make it a Dime-size mark. Don't put too much water, just enough to say that the card isn't dry, but not enough to discolor it. Now hold the card at an angle so that you do not see any light reflection from the wet spot. Just blur your eyes as described above and you should see the mark. Of course this simulated mark will quickly disappear since it is just water but it will still give you the experience. You will notice that the card looks completely plain when looked at in focus, and yet the marks show up when you blur your vision.

In the late 1990s several outlets have started selling "juice" over the Web. There are several web sites that carry the exact same product, which is easily recognizable because it is always labeled "The Juice" and it features a stick-figure cartoon character. Fortunately (or unfortunately, depending on how you look at it) this commercial juice is not the same substance that cheaters have managed to keep under the hat for decades.


The chapter on juice work would be incomplete if I did not mention that there is a way to juice a card without using any chemical substance at all. The beauty of this chemical-free method is in its simplicity. What makes this method possible is a completely natural occurrence. However, to make use of this natural occurrence one must go through the process of inducing it upon select areas of the cards. Unfortunately, this method is too good to pass on to the general public so this is where I have to end it. Just as a clue it won't hurt to mention that this method is probably more popular in Las Vegas than it is in Atlantic City.



Counterfeit Bee cards Counterfeit Bee cards
Finally, there is another type of work that is easier to view by throwing your eyes out of focus. This work is found on the backs of Connell Bros. counterfeit Bee cards (described under the Cards Marked By Manufacturers heading).

Although the Connell Bros. counterfeits do not have juice marks, the work will stand out when viewed out of focus. The two images on the right are both the same scan of an actual Connell Bros. counterfeit Bee, except that the image on the far right has been defocused. Although the details of the work are lost due to the limitations of the resolution of the monitor, the work can still be seen on the focused image, if you force your eyes to look out of focus.

The theory behind the principle that brings the image to life, when viewed out of focus, is different from the theory behind juice marks. In this case entire rows of white diamonds have been enlarged. This reduces the thickness of the printed lines between the white diamonds and when the image is not in focus the enlarged white diamonds "bleed" into the thinned-out liners of print. This makes an entire row of white diamonds blend together more than the rest of the rows, which makes them appear as a fatter white area, or in this case, as a line.

This precision work would probably be impossible to put-on the cards by hand; or at least it would not be practical or cost effective. The work on the counterfeit Connell Bros. Bee cards was put-on the actual printing plates, at the factory. Although the work is quite clever, if not ingenious, it is basically unusable because the quality of the counterfeit cards is too poor to make them pass as genuine Bees and the work itself is a tad too strong to be used at any serious level. Too bad.




3D marked cardPerhaps these cards could have been included under the Cards Marked By Manufacturers heading but I wanted to mention them after explaining juice work.

These cards are marked with large letters and numbers across their backs. To view them you have to stare at them by diverging your eyes and refocusing on the hidden image. Once you manage to refocus on the hidden image the markings will look three dimensional. The cards bear a repeating pattern that has been encoded with a hidden image. Such patterns are scientifically called Single Image Random Dot Stereograms. The same principle is used in Magic Eye™ stereograms which became popular in the early 1990s. The idea is of course much older. In fact, in the 1960s extensive research of random dot stereograms was conducted by Dr. Bela Julesz. If you are interested in this science you may want to visit your local book store.

The card on the screen is the Ace of Clubs. To view it just stare at it for awhile and allow your eyes to wonder apart until they start to focus onto the deep image. You soon should be able to see a large "A" and a "Club" icon next to it. This mark is on the upper third of the card and is repeated on the bottom third (flipped).

Since it takes a long time to focus onto the hidden image these cards are not at all practical for cheating. A cheat has to read the backs fast without arousing suspicion. Another reason why they can't be used in a serious game is because they don't even look like real cards. This is a novelty product and this is really what they are used for. Just for fun! Interestingly enough, these cards do not pass the riffle test because every single card has a different computer-generated random dot pattern.





This is one of the most high-tech card-marking system to date. In fact, it cannot function at all without special electronic imaging equipment. The system currently sells for about $10,000 (it used to cost $20,000 when it was first invented) and is usually used in "friendly" home games, or in after-hours clubs that run illegal gambling games.

marked cards: video juice marked cards: video juice
The cards are marked with a special chemical that leaves an invisible residue. Unlike any other marking method, this time the marks are truly completely invisible to the eye. Unlike conventional juice, no amount of eye-training exercises will ever enable any human to see those marks, yet the same marks are clearly visible through a specially modified video camera. The image on the left is a still that was taken through a regular video camera, and the image on the right was shot through the special camera. Incidentally, both cameras that were used to capture these images were the exact same brand and model; the only difference was that one of them has been modified for viewing the juice marks. As you can see, the cards might as well be dealt face up. The video demo is listed in our "video archive," under the video-juice camera system page.

The basic principle of this scam is very simple. A cheat monitors the game on a TV monitor located in a hidden room and then signals the information to one of the players at the card table. So, in order to work this scam the cheaters have to resolve three technical issues: the ink, the camera, and the communication.

The ink is a special substance that will only be visible through a specially modified video camera. First of all, this ink should no be confused with the ink used for the old luminous readers gadget; the secret of the video juice system is not just faint green ink and a video camera with a red lens. In fact, luminous ink and a red filter will not work at all with a video camera. I tried.

There are several substances that may be used to make the ink. The substance that I currently prefer is made by diluting a very small amount of special powder in a solvent. The powder is a substance that is made for industrial purposes and actually happens to be very expensive. I have only been able to find distributors of this chemical that sell it in bulk, with a $5,000 minimum order. Partly through luck and partly through schmoozing I was able to find a source that was willing to sell a small sample to me.

One big advantage of the particular chemical that I found is that it will not show up under a black lamp. Black lamps are generally used to detect forgeries and art restorations; in gaming security they are used to detect certain marks on playing cards, namely juice work. Some of the other inks that can work for video juice will also show up under a black lamp. This is obviously a big flaw because the juice can be detected without the special camera. This factor alone played an important role while I was developing my own ink solution.

The camera is a specially modified video camera. Depending on the specific type of camera some will require either one or two modifications. Furthermore, some video cameras can not be adequately modified for this system. To work the scam the special camera can either be strategically hidden somewhere above the card table, or even pose as a security camera. Ironically, it is almost like the eye-in-the-sky in the casinos.

The last important technical issue is the communication between the cheats. The simplest setup will involve only two people: the plant and the spotter. The plant is seated at the card table and pretends to play the game. The other cheat, the spotter, is in another room; he records the distribution of the cards on a video recording system, then if needed studies a slow-motion playback on a TV monitor, and then sends secret signals to the dummy player.

The actual communication can be established through a wireless earpiece, a buzzer, or even light signals. Some setups involve a third person who will wear the wire and be strategically located in the room so that the dummy player can receive hand signals. In this case this person might as well wear a cell phone with an ear piece. I doubt anyone would pay any attention to someone who is not part of the game. The hand signals between the guy wearing the wire and the dummy player can be very simple. All the player needs to know is when to fold, check, call, raise, or re-raise; the actual playing decisions can be made by the guy watching the game on TV. In fact, sometimes simplicity is the best solution. All that the player really needs to know is whether or not he has the highest hand.


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