Seaglass Cardigan: Inset Mosaic Crochet Pattern

Elevate your handmade wardrobe with the elegant
and eye-catching Seaglass Mosaic Cardigan — a truly unique
piece that blends timeless style with modern crochet
techniques.

Woman with long brown hair wearing a Seaglass Mosaic Cardigan and jeans, standing indoors in a well-lit living room.

Project Overview

The Seaglass Cardigan is an elegant statement piece that blends timeless style with modern inset mosaic crochet for stunning colourwork without carrying yarn or weaving in tails. Designed in luxuriously soft merino wool with a beautiful tonal teal effect, it features a chic cropped length, relaxed sleeves, snug cuffs, and a polished button up front with gold accents. Available in sizes XS to 5X, this eye catching yet wearable cardigan includes a step by step video tutorial to guide you through the construction.

Skill level: Intermediate

Sizes: XS-5XL

Yarn Weight: Sport Weight # 2

Yarn: Bella Coco Merino Sport Weight #2,

Hook Sizes: US G/6 (4mm) US E-4 (3.5mm) Hook Tray

Construction: Worked in three pieces, Bottom-up

Video Tutorial: https://youtu.be/2LhvnYCYhys

Designed using inset mosaic crochet, this pattern delivers stunning colourwork without the hassle of weaving in tails or carrying yarn, making it both beginner-friendly and rewarding to create.

Crafted in the luxuriously soft Bella Coco Merino Wool, the Seaglass Cardigan showcases a beautiful, gradual teal blue print that adds depth and dimension to every stitch. The yarn’s gentle drape complements the cardigan’s chic cropped length, relaxed sleeves, and snug cuffs, creating a silhouette
that’s both flattering and comfortable.

Finished with a button-up front and elegant gold buttons, the Seaglass Cardigan strikes the perfect
balance between cozy and classy. Whether dressed up or down, this high-end piece is sure to turn heads
— a statement cardigan you’ll reach for again and again.

The pattern includes sizes XS–5X and comes with a step-by-step video tutorial to guide you through the
construction details.

Woman with long brown hair wearing a light blue Seaglass mosaic cardigan and white top, standing indoors on wooden flooring near a chair and shelves.

Yarn Requirements

Bella Coco Merino Sport Weight #2,

180yds/50g, 100% Wool in, Coastal Drift and Ivory

*See the size chart for yardage

Size Chart & Yarn Requirements

Please note that this design is a classic fit with positive ease. When selecting your size, refer to your preferred Finished Bust Measurement. Size up or down as needed for desired fit. Due to the pattern repeat some sizes are combined. For reference, the model is wearing a medium with a 36″ bust and is 5 feet 6 inches tall.

Please note that yarn amounts are estimates and may vary slightly between different yarn brands and individual tension. It’s always a good idea to have a little extra yarn on hand to avoid running out during your project. Happy crocheting!

Two knitted panels with a turquoise and white geometric pattern, inspired by the Seaglass Mosaic Cardigan, are displayed on a white surface beside yarn balls and white flowers. A hand holds one panel at the bottom edge.

Skill Level

Intermediate, written in standard American terms.

Mosaic crochet knowledge is recommended for the Seaglass Cardigan crochet pattern.

Gauge

Body Mosaic: 24.5 sts and 29 rows equal to 4″ in mosaic pattern with 4mm hook

Ribbing: 15 sts and 14 rows equal to 2″ in sc blo with 3.5mm hook

I’ve included some yarn recommendations that would serve as excellent alternatives for this project!

A variety of colorful yarn balls are arranged in a neat cluster on a white surface, perfect for your next Mosaic Cardigan project, with greenery and a woven mat partially visible on the left side.

Suitable Yarn Substitutes for Bella Cocoa Merino

Mandala String Yarn 350yds/100g

Farmhouse Cotton 360yds/100g

Hawthorne Fingering 357yds/100g

Stroll 231yds/50g

Sandscapes 328/100g

Before starting your project, it’s important to create a gauge swatch. This step ensures your tension and stitch count match the pattern specifications — especially crucial if the original recommended yarn is unavailable or if you’re making a yarn substitution. Achieving the correct gauge is essential for getting the intended fit and drape.

If your gauge is off, try adjusting your crochet hook size or even switching the hook style or brand. Keep in mind that not all yarn weights are exactly the same, even when labelled identically; differences in thickness, drape, and softness can occur.

For this pattern, I recommend crocheting the mosaic section with a 4mm hook, following the chart and directions on page 10 of the PDF pattern. Measure your stitches at the centre of the swatch. If you have too many stitches, move up to a larger hook size; if you have too few, switch to a smaller hook. You can also fine-tune stitch height with your technique — lengthen stitches by pulling up slightly, or shorten them by tightening your tension.

I’ve included some yarn recommendations below. While they may be listed under different weight categories, I’ve chosen them based on yardage per gram to closely match the Bella Coco Merino. I’ve found the sport weight used in this pattern to be on the lighter side, so these alternatives should give a similar result.

A woman with long brown hair stands indoors, facing away, wearing a Seaglass mosaic cardigan sweater and high-waisted blue jeans.

Crochet Hooks Required

US G/6 (4mm)

US E-4 (3.5mm)

Hook Tray

Woman with long brown hair wears a Seaglass Cardigan in light blue and white patterns with high-waisted jeans, standing indoors and looking down.

Materials Needed

6-8 Blocking Mats 24″x 24″

Woolwash

Woman standing indoors, smiling at the camera in a Seaglass Mosaic Cardigan and light jeans. Shelves and a potted plant are visible in the background.

Abbreviations

Blo – Back Loop Only

Ch – Chain

Dc – Double Crochet

Pm – Place Marker

Rep – Repeat

RS – Right Side

Sc – Single Crochet

Sc2tog – Single Crochet Decrease

Sk – Skip

Sl St – Slip Stitch

Sp(s) – Space(s)

St(s) – Stitch(es)

WS- Wrong Side

( ) – Work step in parentheses in indicated stitch

[ ] – Work step in brackets the number of times indicated

Special Stitches:

Mdc – Mosaic Double Crochet – A drop down dc is worked as a double crochet that is worked into the skipped st 3 rows below. It is indicated by an X on the chart. This stitch is worked on the RS of the garment. To prevent loose chains on the WS of work, you can anchor them by working the dc st around the chains. See the video for a demonstration.

Sc2tog – Single Crochet 2 together – Insert hook through indicated st and pull up a loop, insert hook in next st, pull up a loop, YO, pull through 3 loops on the hook.

Woman with long brown hair wearing a light blue seaglass-patterned cardigan and denim skirt stands indoors, smiling at the camera. Shelves and a chair are visible in the background.

Construction

The Seaglass Cardigan is constructed in three pieces and worked from the bottom up. Begin by crocheting the back panel. At the top of the back panel, chains are added to each side to form the sleeves.

Next, the front panels are worked as two separate pieces. As with the back, chains are added at the top of each panel to shape the sleeves.

Once all three pieces are complete, block them before assembly. Seam the shoulders and sleeves together first, then join the side and underarm seams. Finish by adding the ribbed collar with buttonholes, and complete the cardigan with ribbed cuffs at the sleeve edges.

A hand holds a knitted turquoise and white patterned fabric, reminiscent of a Mosaic Cardigan, with matching yarn balls and white flowers arranged nearby on a flat surface.

Video Tutorial

Join me and follow along to this detailed tutorial to complete the Seaglass Mosaic Cardigan pattern in size medium.

Subscribe On Youtube

Upgrade to the Premium PDF Pattern!

Digital PDF Download

Etsy

Ravelry

Fourthwall

Digital pattern only. No physical item will be shipped.

FAQ & Terms

Terms & Conditions

This post may contain affiliate links. Purchases made through these links may earn MJ’s Off The Hook Designs Inc. a small commission at no extra cost to you. Content on this site is supported by ads—please do not block or remove them.
Copyright
All patterns, photos, and written content are the property of MJ’s Off The Hook Designs Inc. and protected by copyright law.
Usage
Free patterns are for viewing only on this blog. You may not copy, download, print, screenshot, or redistribute any part of the pattern. Access must remain through this page with ads visible. Use of ad blockers, reader view, or any similar tools that remove or hide ads and site content is strictly prohibited.
Legal Notice
Unauthorized reproduction or distribution may result in copyright infringement penalties.
By accessing this post, you agree to these terms and conditions.

Can I sell my Finished Product?

Yes! You may sell finished items made from MJ’s patterns, but please credit:
“Pattern by MJ’s Off The Hook Designs Inc.”

Where can I get help with a pattern?

Pattern Support is only available in our Facebook Community group and Video Tutorials.
No additional support is provided for modified patterns, alternate yarns, or changes to gauge.

Having trouble unlocking the pattern?

If you’re seeing the message “Email subscription failed, please try again”, don’t worry — it’s usually an easy fix! Here are a few quick things to try:
First, double-check your login details. Make sure you’re signing in with the same email you originally used to create your Grow account. If you’re not sure, click “Forgot Password” to reset your login. Once you’ve updated it, return to my site and try again.
Next, clear your browser’s cache and cookies. Sometimes the login just gets stuck. You can also try opening the page in a private or incognito window, or switching to another browser like Chrome, Safari, or Firefox to see if that does the trick.
It also helps to make sure you’re logged into Grow directly. Visit https://grow.me and sign in there first. Once you’re logged in, come back to my site and refresh the page — your pattern should unlock automatically.
If you’re still having trouble, check your browser’s privacy settings. Grow needs cookies to verify your account, so make sure cookies and cross-site tracking are allowed. On iPhone, go to Settings → Safari → Privacy & Security, then turn off “Prevent Cross-Site Tracking” and “Block All Cookies.” On Android or Chrome, go to Settings → Site Settings → Cookies and select “Allow all cookies.”
Lastly, ad blockers or browser extensions can sometimes block the login pop-up. Try turning them off temporarily while you sign in. If nothing seems to work, log out of Grow completely by going to https://grow.me, selecting your profile icon, and choosing Log Out. Then come back to my site and try logging in again.
If you’re still stuck after trying all of this, please reach out through my Contact Page and let me know what device and browser you’re using (and include a screenshot if you can).

Woman with long brown hair wearing a Seaglass Mosaic Cardigan and jeans, standing indoors in a bright living room with wooden floors and shelves in the background.

To unlock Exclusive Content on my Blog, all you need to do is click the box below and the Grow.me app will pop up, allowing you to enter your email and create a password. Once you’ve created an account, every time you see Exclusive Content on my blog, simply login to your Grow account. Be sure to switch to the login screen to enter your login credentials.

If you forget your password, click the “forgot password” link and follow the prompts. Please note that I’m unable to assist with resetting Grow passwords or accessing your Grow account, so be sure to save your login information in a safe place.

To make things even easier, I’ve created a video for both desktop and mobile users that offer additional assistance. You can access this video by visiting my FAQs page HERE or by watching the video below.

Thank you for subscribing and for joining me on my crochet journey. I hope you enjoy the exclusive content available to our subscribers and create beautiful crochet projects using the resources you discover.

If you enjoyed this pattern, you may also like these patterns:

This pattern is designed by Michelle Moore of MJ’s Off The Hook Designs Inc, based in Lakefield, Ontario, Canada. Your go-to source for modern, easy crochet patterns. Published on August 13th, 2025.

Thank you for visiting MJ’s Off The Hook Designs. I hope you enjoyed this pattern and feel inspired to pick up your hook and start creating.

You can find even more crochet patterns in our Ravelry and Etsy shops.
For daily inspiration and behind-the-scenes peeks, join me over on Facebook or Instagram, or join our YouTube Membership for exclusive content!