Not All Resins Are Created Equal: Comparing Epoxy, Polyurethane, and Jesmonite Materials
Not all resins are created equal and that’s a good thing!
Today’s creative material landscape includes everything from glossy epoxy systems to industrial casting plastics and water-based mineral composite materials like Jesmonite® AC100. While many of these products are grouped together under the label “resin,” they are often designed for very different applications, finishes, workflows, and studio environments.
Some materials are best known for crystal-clear coatings and river tables. Others are engineered for fast industrial prototyping and mold casting. Water-based mineral composite systems like Jesmonite® AC100 offer a different experience altogether, featuring matte stone-like finishes, fast demolding, low odor workflows, and decorative casting versatility.
Each material family comes with its own strengths, tradeoffs, tools, and ideal applications.
So rather than asking, “Which resin is best?” a better question might be: Which material system is best for the way you like to create?
In this guide, we’re taking a closer look at three major material families creators commonly work with today:
- Traditional epoxy resins
- Polyurethane casting resins
- Water-based mineral composite resins
We’ll compare how they look, how they behave, what tools they require, and the types of projects they are best suited for so you can better understand which material fits your creative process, workspace, and finished aesthetic.
Understanding the Three Major Resin Material Families
Not all resin systems are built around the same chemistry. The material composition directly impacts how a product cures, behaves, finishes, and performs.
Today, most creator-focused casting materials fall into three broad categories:
Traditional Epoxy Resins
Traditional epoxy resins are thermosetting polymer systems made by combining a resin with a hardener. Once mixed, the two components chemically react and cure into a rigid plastic material.
Epoxy systems are typically known for their self-leveling behavior, transparent appearance, and strong adhesive properties.
Polyurethane Casting Resins
Polyurethane casting resins are reactive plastic systems created by combining two liquid components that cure into a solid material. These systems are commonly formulated for fast curing, dimensional accuracy, machinability, and industrial-style casting performance.
Depending on the formulation, polyurethane materials can range from rigid plastics to flexible rubber-like systems.
Water-Based Mineral Composite Resins
Water-based mineral composite systems combine an acrylic polymer liquid with a mineral-based powder to create a durable casting material with a stone-like appearance. Jesmonite® AC100 falls into this category.
Unlike traditional epoxy or polyurethane systems, water-based mineral composites contain a high mineral content, which contributes to their opaque appearance, texture, and surface characteristics. These systems are typically water-based rather than solvent-based and cure into dense decorative composite materials rather than transparent plastics.
Comparing Aesthetics and Finish
One of the biggest differences between resin material families comes down to appearance. The finish you want for your final piece will often determine which material system makes the most sense for your project.
Traditional Epoxy Resins
Traditional epoxy resins are best known for their glossy, glass-like appearance and transparent finish. These systems are often chosen for projects that prioritize depth, shine, clarity, or encapsulation effects. Because epoxy cures clear, it can create layered visual effects and is commonly tinted with translucent dyes, alcohol inks, mica powders, and pigments. The smooth self-leveling surface also contributes to the polished appearance epoxy is known for.
One thing creators often consider with epoxy systems is long-term UV exposure. Depending on the formulation and environment, clear epoxy surfaces can yellow over time, especially in direct sunlight or outdoor applications.
Polyurethane Casting Resins
Polyurethane casting resins are typically more focused on precision and surface detail than transparent decorative finishes. Most systems cure opaque rather than crystal clear and are often designed to replicate fine textures and mold details with high accuracy. The final appearance of polyurethane castings often depends heavily on post-processing techniques such as sanding, painting, machining, or surface finishing after cure.
Compared to epoxy systems, polyurethane materials are generally associated with industrial-style finishes, painted surfaces, and production-oriented casting applications.
Water-Based Mineral Composite Systems
Water-based mineral composite systems, like Jesmonite® AC100, are known for their matte, opaque, stone-like appearance and highly adaptable surface aesthetics. Unlike transparent epoxy systems, water-based mineral composites can be finished to resemble stone, concrete, ceramic, terrazzo, plaster, and other natural mineral surfaces.
Jesmonite® is often referred to as a “chameleon material” because of its ability to replicate a wide range of colors, textures, and surface finishes. Depending on the pigments, fillers, molds, and finishing techniques used, Jesmonite® can mimic the appearance of stone, concrete, ceramic, terrazzo, plaster, wood, and even textiles.
While the material naturally cures to a matte finish, the final appearance can vary significantly based on finishing techniques. Sanding, polishing, waxing, or applying sealers can dramatically change the look of the surface. A gloss sealer, for example, can create a polished, reflective finish while still maintaining the character of a mineral composite material.
Comparing Workflow & Creator Experience
While many casting materials may appear similar once fully cured, the hands-on experience of working with each material family can feel very different. Working time, cure speed, cleanup methods, moisture sensitivity, and finishing techniques all influence how creators approach their projects and studio setup.
Some materials are designed for slower, detail-oriented workflows that prioritize transparency and surface finish. Others are optimized for fast production casting and rapid demolding. Water-based mineral composite systems like Jesmonite® AC100 introduce another type of workflow that focuses more heavily on surface design, pigmentation, texture, terrazzo techniques, and decorative finishing.
The table below highlights some of the most common workflow differences creators may encounter when working across these material families:
These differences are not necessarily advantages or disadvantages. They simply reflect the priorities each material system was designed around.
For example, creators working with traditional epoxy systems may spend more time managing bubbles, layering pours, or achieving high-gloss finishes. Polyurethane casting systems are often optimized for speed and production efficiency, which can require faster working methods and tighter environmental control.
Water-based mineral composite systems, like Jesmonite® AC100, typically offer shorter demold times and water-based cleanup while also supporting a wide range of decorative finishing techniques. Because these materials are opaque rather than transparent, the workflow often centers less on achieving crystal-clear pours and more on texture, pigmentation, surface finishing, and mold design.
Comparing Tools & Workspace Requirements
Different material systems often require very different workspace setups and tools. Some creators prefer slower decorative workflows with minimal equipment, while others prioritize rapid production casting or industrial-style fabrication environments.
Traditional epoxy systems commonly involve tools such as torches, mixing stations, sanding equipment, and ventilation support. Polyurethane casting systems may require tighter environmental control, moisture management, and production-oriented setups.
Water-based systems, such as AC100, are often associated with lower-odor decorative casting workflows and water-based cleanup while still supporting a wide range of finishing techniques and studio applications.
The table below highlights some of the most common tools, workspace considerations, and environmental factors creators may encounter when working across these different material families.
Comparing Durability & Performance
Performance expectations can vary significantly depending on the material family, formulation, and intended application. Some systems prioritize transparency and surface finish, while others are engineered around dimensional stability, production efficiency, decorative durability, or architectural-style performance.
The table below highlights some of the most common durability and performance characteristics associated with each material family.
Traditional epoxy systems are often valued for their glossy appearance and coating properties but may require consideration around UV exposure and long-term yellowing depending on the environment and formulation used.
Polyurethane casting materials are commonly associated with impact resistance, machinability, and fast production performance. Many systems are designed for industrial fabrication workflows where sanding, painting, machining, and post-processing are common parts of the finishing process.
Water-based mineral composite systems like Jesmonite® AC100 combine decorative surface versatility with dense mineral-based characteristics that support a wide range of interior, sculptural, and architectural-style applications when properly sealed and finished.
Choosing the Right Material for Your Creative Process
At the end of the day, no single resin system is designed to do everything.
Traditional epoxy resins, polyurethane casting resins, and water-based mineral composite systems were all developed around different priorities, finishes, workflows, and applications. The best material for one project may not be the best fit for another.
Some creators prioritize crystal-clear finishes and high-gloss surfaces. Others need rapid curing, precision casting, or industrial-style durability. Many are drawn to matte mineral aesthetics, decorative versatility, terrazzo techniques, and sculptural surface finishes.
The good news is that creators today have more material options than ever before.
Understanding how these material families differ can help you make more informed decisions about:
- the look you want to achieve,
- the tools and workspace you want to work in,
- the pace of your workflow,
- and the overall creative experience you enjoy most.
Rather than asking which material system is “best,” it’s often more helpful to ask: Which material best supports the way you like to create?
If you’d like to learn more about Jesmonite® AC100, visit our Resources page for product information, tutorials, project inspiration, and educational guides designed for creators.
Explore Jesmonite® AC100 Resources: HERE
