Sea Glass Mosaic — How To Make Art with Beach Glass
By Kenneth Blaine
Greetings from Southeast Puerto Rico! I have been an avid beachcomber for most of my life, and like many fellow readers, I am captivated by sea glass and the endless hunt for the next best piece.
If you’re a die-hard beachcomber like me, you’ve accumulated a ton of glass over the years. Perhaps you enjoy sorting it by color and size or by grading it based on condition and perfection.
With every jar and display vessel I have filled from years of beachcombing, I grew tired of simply accumulating. Yes, they are beautiful and display great, but what about all the pieces that aren’t seen? Many sea glass collectors eventually turn to a variety of crafts and art-forms with their finds—jewelry, flat lays, photography, 3D trees, framed arrangements, and more.
As for me, I fell in love with the art form of mosaics through sea glass. It began with arranging pieces to create shapes, animals and flowing lines and then photographing them. Of course, a very peaceful and forgiving creative practice. But once the arrangement was photographed, the glass was simply put back into the jar or bin. I was longing for something more permanent, and I wanted to use up a volume of excess collected glass in common colors, particularly clear sea glass.
At first, I taught myself how to make mosaic serving trays. I scoured the internet for how-to videos and came across a variety of them through sites like YouTube and Pinterest. Unfortunately, most free online mosaic art content gives wrong advice whether in the materials needed, adhesives, grout or even the substrate (the surface your mosaic is adhered to). Always be careful with using wood—learned that the hard way! Some of my original mosaics have since cracked and crumbled and I regret not seeking formal instruction sooner. The trial-and-error phase of my sea glass mosaic journey was painful, especially for pieces that took countless hours to make only for them to deteriorate.
I quickly sought mentorship with professional artists, and over time adjusted and developed my own processes as a result. Processes that implement proper substrate preparation, using correct adhesives for both indoor and outdoor applications in various climates, correct grout types and liquid fortifiers to avoid deterioration, techniques to even skip grouting altogether, working in 3D, using colorful pigments, etc. Learning the professional foundations of creating mosaics for permanence has been a game changer in my artistic development and career.
The art form of mosaics is endless, encompassing everything from micro-mosaic jewelry, stained glass works, mixed media projects, and traditional Roman methods to home installs, murals, sculptures, fountains, and pools. It is an unlimited medium, which is why so many art lovers get hooked. It becomes a choose-your-own-adventure of learning while simultaneously developing your own artistic voice. In 2024, I took the deep dive into mosaic art instruction and am now the sea glass mosaic expert with Mosaic Arts Online, an online platform for learning mosaics. Following are the main steps for creating a mosaic using your sea and beach glass.
When creating mosaics with sea glass, there are multiple stages involved from start to finish, all super fun!
1. Prepare your subject
One of the key components of successfully creating a beautiful mosaic is planning. I like to set aside time each week to simply sit down with a pile of sea glass in front of me and arrange pieces together in ways that are aesthetically pleasing. This could be building simple lines or swirls, exploring color contrasts, or creating figurative subjects. My favorite creations include sea turtles and other coastal animals and objects. Once you are satisfied with a particular arrangement or design, you may wish to incorporate it into a mosaic. As pictured, I have arranged a small baby sea turtle using just ten pieces of green sea glass—simple enough, right?
2. Choose your substrate
As previously mentioned, a substrate is the surface on which your mosaic will be made. For newbies or those with a limited supply of sea glass, it is great to start small. Working in 4x4 or 6x6 inch mosaic frames are always great as they do not take endless hours to create or use up your entire collection of glass. Of course, as you build experience and take on more elaborate design ideas, going big is a great option too. For starters, small substrates are more approachable.
3. Mix adhesive and prepare your substrate
When making mosaics, I work exclusively with a variety of mortars, mixed in small batches. I do not recommend using mastic. It is always important to wear safety glasses and a mask when mixing adhesives and grouts and best to avoid making a mess of your hands as well. Once mixed, you may remove the mask and glasses.
Once the mortar is mixed to the correct consistency and slaked (rested so the mortar ingredients hydrate and bond), you may begin working it into your substrate. As you are working, it is important to apply a “scratch coat” which will ensure a strong bond between your sea glass and the substrate, avoiding air pockets or gaps that could weaken your mosaic.
4. Adhere your sea glass
Once you have your subject laid out and your adhesive mixed, you can begin placing your sea glass onto the substrate. Working from the center in, build a bed of mortar and apply your sea glass. The fun part about this process is that once the sea glass is laid into the cement, you can use your tools to adjust alignment to your liking while the mortar is still wet. Continue working in small sections at a time until your mosaic is finished. Do not rush through this. If your mortar begins to harden or become difficult to work with, take a break and clean up around your unfinished space. You can always mix another batch of mortar and continue working. This is one of the best perks of making mosaics. You can work on it as little or as much as you’d like. Once the mosaic is complete, it is important to let it rest and cure at least 24 hours prior to grout application.
5. Grout your mosaic
Grouting sea glass can be daunting! Most mosaic artists avoid it and dislike sea glass. Sea glass is typically very porous and so you will find that it is inevitable for some grout to end up in the pitted sections of your glass. This isn’t a major deterrent for me. Take your time to clean it away, using as little water as possible with a combination of dry rags and a sponge. Once the grouting phase is finished, your piece is done!
Allow ample time for your mosaic to rest so the grout will dry undisturbed. You can then go over it with a soft rag and touch up any dusty spots if needed. Display it proudly anywhere you like or perhaps use as a thoughtful gift for a loved one.
And that’s a wrap!
While the overall process of creating a sea glass mosaic may sound challenging or even overwhelming, I assure you that once you dive in you will find it to be fun and rewarding. Making mosaics is all about slowing down. Like a sea turtle, it is not rushed. Creating mosaics with your sea glass is meant to be enjoyed in the moment, finding joy in the experience of the process as much as the satisfaction in your finished product. Again, as the whole creative process is broken down into several steps, mosaic making becomes a very manageable project taken at your own pace. Break out your sea glass collection, perhaps give my mosaic course a try, and most importantly—be creative!
Go at your own pace
If you are interested in taking a class on mosaic making before committing your sea glass to be grouted permanently in place, consider enrolling in Kenny’s course through Mosaic Arts Online (MAO)at mosaicartsonline.com. The course is organized in step-by-step “chapters” with live video recorded demonstrations of the entire process. “What I love the most about the MAO platform is that you can stop and go at whatever creative speed is most suitable for you,” Kenny says.
During the class, Kenny walks you through all the steps to make a sea glass mosaic, including a PDF with a list of supplies he recommends, instruction on how to sort and select sea glass, and all the steps to assemble and grout your mosaic. “My course also places strong emphasis on safety as you work—something that is not always explained properly,” Kenny adds. Don’t have enough sea glass? Kenny can also recommend where you can purchase genuine sea glass to use in your piece.
Discount for Beachcombing readers
Use coupon code BCMAG10 at www.mosaicartsonline.com to take advantage of a course discount that Kenny is generously offering to Beachcombing readers.
Happy mosaic making!
Make art with your beach finds
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This article appeared in Beachcombing Magazine Volume 49, the July/August 2025 issue.
