Ivory, a coveted material prized for centuries, possesses an allure that has made it a favorite among artisans and collectors. However, the distinction between genuine ivory and its many imitations can be a daunting task. Skilled craftsmen have mastered the art of creating convincing replicas, making it imperative to possess the knowledge and tools to discern the genuine article from its counterfeits.
The tactile experience plays a crucial role in identifying ivory. Genuine ivory exhibits a unique waxy feel, smooth to the touch and devoid of the graininess often associated with substitutes. Its surface is warm and slightly pliable, yielding slightly under gentle pressure. Moreover, the color of ivory ranges from creamy white to a rich, antique hue, and often exhibits a subtle translucency when held against the light. These tactile attributes provide valuable clues in distinguishing real ivory from its imitations.
In addition to its physical properties, examining the carving techniques employed can shed light on the authenticity of ivory. Genuine ivory is typically carved with meticulous precision and fine detail, reflecting the skill and patience of the artisan. The lines are crisp and fluid, creating a sense of elegance and refinement. Conversely, imitations often exhibit imperfections in carving, such as uneven lines or rough surfaces, indicating a lack of craftsmanship. Scrutinizing the carving techniques can provide valuable insights into the origins and authenticity of the ivory in question.
Physical Characteristics
Identifying ivory can be crucial for conservation and legal purposes. Here are some key physical characteristics:
Color and Appearance
Ivory’s color ranges from creamy white to pale yellow, depending on the species and aging. It has a smooth, polished surface with a subtle sheen. Unlike bone, ivory lacks visible pores or blood vessels.
Texture and Hardness
Ivory has a fine, homogeneous texture that feels smooth and dense to the touch. It is harder than bone, with a Mohs hardness of around 2.5 to 3.0. This means it can be scratched with a knife or a sharp object but not easily shattered.
Grain Structure
Ivory exhibits a distinctive grain structure known as Schreger lines. When viewed under magnification, these lines appear as a series of parallel lines or arcs that intersect at a characteristic angle. Schreger lines are unique to ivory and can help differentiate it from other materials.
Other Characteristics
Additional physical characteristics of ivory include:
- Translucent: When held up to a light, ivory allows light to pass through, appearing translucent.
- Pyroelectric: Ivory develops an electrical charge when heated, which can be detected with specialized equipment.
- Age-related Patina: Over time, ivory develops a natural patina that imparts a yellowish or brownish tint.
Table summarizing Ivory’s Physical Characteristics
| Characteristic | Description |
|---|---|
| Color | Creamy white to pale yellow |
| Appearance | Smooth, lustrous surface |
| Texture | Fine, homogeneous |
| Hardness | Mohs hardness of 2.5-3.0 |
| Grain Structure | Schreger lines |
| Translucency | Allows light to pass through |
| Pyroelectricity | Develops an electrical charge when heated |
| Patina | Develops a yellow or brown tint with age |
Color and Texture
Ivory is typically a creamy white color, although some pieces may have a faint yellow or pinkish tint. The color can vary depending on the age, origin, and treatment of the ivory. Older ivory tends to be darker and more yellowed with time, while newer ivory is typically whiter.
Texture
Ivory has a smooth, dense, and slightly porous texture. It is hard and durable, but it can be scratched or damaged if not handled carefully. The texture of ivory can vary depending on the species of animal from which it came. For example, elephant ivory is typically harder and denser than mammoth ivory.
Ivory can be distinguished from other materials by its unique combination of color, texture, and density. It is important to note that ivory can be dyed or treated to alter its appearance, so it is important to be aware of these techniques when identifying ivory.
The following table summarizes the key characteristics of ivory:
| Characteristic | Ivory |
|---|---|
| Color | Creamy white, may have a faint yellow or pinkish tint |
| Texture | Smooth, dense, and slightly porous |
| Hardness | Hard and durable, but can be scratched or damaged if not handled carefully |
| Density | High, typically between 1.7 and 2.0 g/cm³ |
Grain Pattern
Examining the grain pattern of an object can provide valuable clues about whether it is made of ivory. Real ivory exhibits a unique grain pattern that distinguishes it from other materials. Here is a detailed description of the grain pattern in ivory:
1. Directionality: Ivory grain lines run in a specific direction, known as the “scrimshaw direction.” This directionality is consistent throughout the object and is not found in imitation materials. When viewed under a microscope, the grain lines in ivory appear parallel and aligned.
2. Crosshatching: Another characteristic of the ivory grain pattern is crosshatching. This refers to the intersecting perpendicular lines that form a diamond-shaped pattern. Crosshatching is a distinguishing feature of ivory and is not observed in synthetic materials.
3. Schreger Lines and Sprinkles: Schreger lines are distinctive microscopic cracks or lines that run perpendicular to the scrimshaw direction. They are visible when ivory is viewed under a microscope or with a high-powered magnifying glass. Additionally, ivory often exhibits small black specks known as “sprinkles,” which are the result of air bubbles trapped during the growth process.
| Characteristic | Real Ivory | Imitation Materials |
|---|---|---|
| Scrimshaw Direction | Consistent, parallel lines | Inconsistent, random lines |
| Crosshatching | Diamond-shaped pattern | Absent |
| Schreger Lines | Perpendicular to scrimshaw direction | Absent |
| Sprinkles | Present (black specks) | Absent |
Density
Ivory is a dense material, with a specific gravity of around 1.9. This means that it is heavier than water and will sink if placed in it. However, ivory is not as dense as bone, which has a specific gravity of around 2.5.
The density of ivory can be used to distinguish it from other materials, such as plastic or resin. Plastic is typically less dense than ivory, with a specific gravity of around 1.4. Resin is typically more dense than ivory, with a specific gravity of around 2.1.
The table below summarizes the specific gravities of ivory, plastic, and resin:
| Material | Specific Gravity | |||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ivory | 1.9 | |||||||||||||||||||||||||||
| Plastic | 1.4 | |||||||||||||||||||||||||||
| Resin | 2.1 | |||||||||||||||||||||||||||
| Fluorescence of Different Materials | ||
|---|---|---|
| Material | Fluorescence Color | Fluorescence Intensity |
| Ivory | Pale blue or green | Strong |
| Bone | White or yellow | Weak |
| Plastic | None | None |
It is important to note that not all ivory will fluoresce. Some types of ivory, such as fossil ivory, may not fluoresce at all. Additionally, some other materials, such as some types of plastic, can also fluoresce. Therefore, it is important to use other identification methods in conjunction with fluorescence to accurately identify ivory.
Scratch Test
The scratch test is a simple and effective method for identifying ivory. To perform this test, you will need a sharp object, such as a knife or needle.
- Gently scrape the surface of the ivory with the sharp object.
- If the surface is hard and does not scratch easily, then it is likely that the object is made of ivory.
- If the surface scratches easily, then the object is probably not made of ivory.
It is important to note that the scratch test is not foolproof. Some materials, such as bone and plastic, can also be hard and difficult to scratch. If you are unsure whether an object is made of ivory, it is best to consult with an expert.
Additional Considerations
In addition to the scratch test, there are a few other factors that you can consider when identifying ivory:
- Color: Ivory is typically white or cream-colored, but it can also be stained or dyed other colors.
- Texture: Ivory has a smooth,细腻 texture that is similar to human skin.
- Grain: Ivory has a visible grain pattern that can be seen when the object is held up to the light.
- Density: Ivory is a relatively dense material. If you hold an ivory object in your hand, it will feel heavier than a similar-sized object made of another material, such as wood or plastic.
- Smell: Ivory has a distinctive smell that is similar to the smell of burnt hair.
Ivory vs. Faux Ivory
There are different types of faux ivories that are made to look and feel like real ivory, the most common types of faux ivory are:
- Polystyrene: Is a lightweight and inexpensive material, and it has poor wear resistance.
- Cellulose Acetate: Is a more durable material than polystyrene, and it has better wear resistance and a more natural look and feel.
- Resin: Is a versatile material that can be molded into a variety of shapes, textures, and colors. Resin faux ivory is often used in the manufacture of jewelry and other decorative objects.
- Bone: Is a natural material that is similar to ivory in appearance, but it is less durable and has a more porous surface.
- Tagua Nut: Is a vegetable ivory nut that is derived from the palm tree Phytelephas macrocarpa. It has a smooth, hard surface and a creamy white color, but it is a little softer than ivory and can be more easily scratched.
- Milk Protein: Is a resilient and durable material that is made by combining milk protein with a resin or polymer. It has a smooth,细腻 texture and a natural creamy white color.
The table below summarizes the key differences between ivory and faux ivory:
| Ivory | Faux Ivory | |
|---|---|---|
| Composition | Natural material derived from the tusks of elephants | Man-made synthetic material |
| Density | 1.7-1.8 g/cm3 | 1.0-1.6 g/cm3 |
| Hardness | 2.5-3.0 on the Mohs scale | 0.5-2.0 on the Mohs scale |
| Solubility | Insoluble in water | Moderately soluble in water |
| Combustibility | Burns with a yellow flame and a pungent odor | Burns with a blue flame and a plastic-like odor |
Thermal Conductivity
Thermal conductivity is a measure of how well a material can conduct heat. The higher the thermal conductivity, the faster the material will transfer heat. Ivory has a thermal conductivity of 0.02 W/m·K, which is significantly lower than that of metals like copper and aluminum. This means that ivory is a poor conductor of heat, and it will not feel cold or hot to the touch.
The low thermal conductivity of ivory makes it an ideal material for use in objects that need to be insulated from heat or cold. For example, ivory is often used in the handles of knives and other tools because it will not transfer heat from the user’s hand to the blade. Ivory is also used in the construction of musical instruments, such as piano keys and violin bows, because it produces a warm, mellow sound.
The thermal conductivity of ivory can be measured using a variety of techniques, including the steady-state method and the transient method. In the steady-state method, a sample of ivory is placed between two thermal reservoirs, and the temperature difference between the reservoirs is measured. The thermal conductivity is then calculated using the following equation:
$$k = \frac{Q}{At\Delta T}$$
where:
- $$k$$ is the thermal conductivity (W/m·K)
- $$Q$$ is the heat flow rate (W)
- $$A$$ is the cross-sectional area of the sample (m2)
- $$t$$ is the time (s)
- $$\Delta T$$ is the temperature difference between the reservoirs (K)
| Material | Thermal conductivity (W/m·K) | |||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ivory | 0.02 | |||||||||||||||||||||||||||
| Copper | 401 | |||||||||||||||||||||||||||
| Aluminum | 237 | |||||||||||||||||||||||||||
| Wood | 0.13 | |||||||||||||||||||||||||||
| Glass | 0.8 | |||||||||||||||||||||||||||
| Water | 0.6 |
| Chemical Test | Purpose |
|---|---|
| Burn test | Distinguishes ivory from other materials |
| Iodine test | Distinguishes ivory from other materials |
| GC-MS | Provides detailed information about the composition of the material |
| HPLC | Provides detailed information about the composition of the material |
| ICP-MS | Provides detailed information about the composition of the material, including the species of elephant from which the ivory came |
Provenance and Documentation
Documenting the provenance, or history of ownership, of ivory is essential for ensuring its legality. This can be done through a variety of means, including:
9. Visual Examination
| Characteristics | Ivory | Plastic/Resin |
|---|---|---|
| Surface Texture | Smooth and often has a slight grain | Smooth but may have a “plasticy” feel |
| Carvings | Sharp and detailed | Often rounded or less precise |
| Aging | Develops a yellow patina over time | Does not age in the same way |
| Weight | Heavy for its size | Lighter than ivory |
Additionally, specific techniques, such as ultraviolet light examination or X-ray analysis, can help distinguish ivory from other materials. Proper documentation should include detailed descriptions, photographs, and any relevant reports or certificates.
Professional Examination
For a definitive identification, consult an expert, such as a gemologist, jeweler, or conservator. Professional examination typically involves:
Microscopic Examination
Examining the ivory’s surface and cross-section under magnification to observe its cellular structure, grain patterns, and any diagnostic features.
Polarized Light Microscopy
Using polarized light to reveal the ivory’s crystalline structure, which can distinguish ivory from other materials such as bone or plastic.
Chemical Analysis
Using chemical tests to detect the presence of certain compounds that are indicative of ivory, such as calcium phosphate and peptides.
DNA Testing
Extracting and analyzing the ivory’s DNA to determine its species of origin and confirm its authenticity.
Fluorescence Analysis
Exposing the ivory to ultraviolet light to observe its fluorescence, as certain types of ivory exhibit characteristic fluorescence patterns.
Density Measurement
Weighing and measuring the volume of the ivory to determine its density, which can help distinguish different types of ivory.
Hardness Testing
Assessing the ivory’s resistance to scratching or indentation to determine its relative hardness, which can vary depending on the species.
Abrasion Resistance Testing
Rubbing the ivory’s surface against a calibrated abrasive to determine its resistance to wear and damage, which can indicate its age and origin.
Burn Testing
Gently heating a small sample of the ivory to observe its reaction to heat, as different types of ivory burn at different temperatures.
Odour Testing
Inhaling the scent of the ivory, as old ivory often develops a distinctive odor due to the oxidation of its organic components.
How To Identify Ivory
Ivory is a hard, white material that is obtained from the tusks of elephants and other animals. It is a valuable material that has been used for centuries to make a variety of objects, including jewelry, sculptures, and musical instruments. However, the trade in ivory is now illegal in many countries, as it is a major factor in the decline of elephant populations. As a result, it is important to be able to identify ivory in order to avoid buying or selling illegal products.
There are a few key characteristics that can help you to identify ivory. First, ivory is very hard and dense. It will not scratch easily, and it will feel smooth to the touch. Second, ivory has a distinctive grain pattern. The grain lines will be parallel to the length of the tusk, and they will be very fine and close together. Third, ivory is translucent. When you hold it up to the light, you will be able to see through it slightly.
If you are unsure whether or not an object is made of ivory, there are a few tests that you can perform. First, you can try to scratch the surface of the object with a sharp object. If the object is made of ivory, it will not scratch easily. Second, you can try to hold the object up to the light. If the object is made of ivory, you will be able to see through it slightly.
If you are still unsure about whether or not an object is made of ivory, you can take it to a jeweler or other expert for appraisal.
People Also Ask
What is scrimshaw?
Scrimshaw is a form of folk art that involves carving or engraving designs into the surface of ivory or bone. It was originally practiced by sailors who would use their spare time at sea to create intricate carvings on the bones and teeth of whales and other marine animals.
How can you tell the difference between ivory and bone?
Ivory is harder and denser than bone, and it will not scratch easily. Bone, on the other hand, is more porous and will scratch more easily. Ivory also has a distinctive grain pattern that is not present in bone.
Is it illegal to buy or sell ivory?
The trade in ivory is illegal in many countries, including the United States. However, there are some exemptions to this law, such as for the sale of ivory that was obtained before the ban on the trade was enacted.
