Seaglass Mosaic Cardigan

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.

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.

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!

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!

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.

Crochet Hooks Required

US G/6 (4mm)

US E-4 (3.5mm)

Hook Tray

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.

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.

Video for the Seaglass Mosaic Cardigan

This video is a companion to the Seaglass Cardigan PDF Pattern and offers step-by-step support for key parts of the project. While it’s not a full tutorial, it will guide you through the essential techniques needed to complete your cardigan. I’ll show you how to crochet the ribbing, demonstrate the inset mosaic crochet technique by working through a few rows, and walk you through adding the left and right sleeves to the body. You’ll also see how to finish the sleeve stitch pattern, seam the cardigan, and add the collar and cuffs for a polished, professional look.

COPYRIGHT

The Seaglass Mosaic Cardigan Pattern and its contents are fully owned and copyrighted by MJ’s Off The Hook Designs Inc., and all rights are reserved. This pattern is protected by copyright and other intellectual property laws and may not be reproduced,

distributed, or transmitted in any form or by any means, including photocopying, recording, screenshots, printing or other electronic or mechanical methods, without the prior written consent of the author, except in the case of permitted sharing on social media platforms.

Any unauthorized distribution or reproduction of this pattern or elements of the instructions is strictly prohibited and may result in civil or criminal penalties. This free crochet pattern is intended for personal viewing on the blog only. By accessing this pattern, you acknowledge and agree to comply with these copyright terms and conditions.

If you have any questions regarding this copyright notice or the use of the pattern outlined within, please contact MJ’s Off The Hook Designs Inc. in writing.

Thank you for respecting the author’s intellectual property and hard work!

Pattern Support

Additionally, please note that the only pattern support offered for this pattern is available on our Facebook community group and through the YouTube tutorial. The modifications given in the PDF are the only ones included, so if you choose to modify the pattern or use a different yarn weight, you will need to figure out the modifications on your own.

We appreciate your understanding and hope that you have a fantastic experience creating this pattern. Please feel free to lend support to fellow members of the community group as we work together to create beautiful crochet projects.

I hope you love making our Seaglass Mosaic Cardigan pattern. You might also love these crochet patterns!

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For more crochet patterns by MJ’s Off The Hook Designs see our Ravelry and Etsy Shop. Check out our Facebook and Instagram for inspiration.