Spring 2027

Gems: the Science Behind the Sparkle

Explores the formation, collection, properties, and treatment of popular gemstones, covering their science and classification.

offering recorded1–2 credits
Recorded instructors · Spring 2027 Huifang Xu3.5/5

Summary

1 / 6

Past student reviews · Huifang Xu

Exams were timed and consisted of 30 questions, requiring students to search through all lectures to find the correct answers.

What you’ll be able to do

  • Recognize common / popular gems and their corresponding minerals in geological environments.

  • Recognize factors that affect the quality and value of gems.

  • Summarize differences among natural gems, enhanced gems, synthetic gems, and simulants.

Source: UW Guide

Grade history

↗
average GPA
letter grades
A
AB
B
BC
C
D
F

All recorded terms · compare terms & instructors

Prerequisites

Course map

Junior standing

  • Junior standing
GEOSCI 331

This is a best-effort interpretation; check the catalog requirements above.

Prerequisite text tree
  • Junior standing

Professors

Spring 2027
Adjusted rating
RMP difficulty
captured reviews
About this rating

Raw average: 3.33/5 from 21 quality ratings. The adjusted rating blends this with the UW review average (3.66/5), weighted as 20 additional ratings. Smaller samples stay closer to that average. Each captured review is counted once in the prior; this does not correct who chooses to leave a review.

For this course: 3.5/5 raw quality · 2.7/5 difficulty · 6 reviews

RMP profile ↗ · All captured review dates; profile matched by name.

Past student reviews · Huifang Xu

Huifang Xu taught GEOSCI 331 as an online course using PDF lectures and timed exams. Students described the assessments as ranging from easy to nitpicky, noting that exams consisted of 30 questions requiring answers from all lectures. Some students reported the class was easy to pass, while others found the questions extremely nitpicky.

Recent recorded grades — Spring 2025: 3.45 GPA, 73.6% A/AB (n=276 letter grades); Fall 2025: 3.76 GPA, 89.7% A/AB (n=234 letter grades); Spring 2026: 3.84 GPA, 92.5% A/AB (n=280 letter grades).

Historical instructors & teaching patterns

HUIFANG XU is recorded teaching in Fall 2006, Spring 2007, Fall 2007, Spring 2008, Fall 2008, Spring 2009, Fall 2009, Spring 2010, Fall 2010, Spring 2011, Fall 2012, Spring 2013, Fall 2013, Spring 2014, Fall 2014, Spring 2015, Fall 2015, Spring 2016, Fall 2016, Spring 2017, Fall 2017, Spring 2018, Fall 2018, Spring 2019, Fall 2019, Fall 2020, Fall 2021, Spring 2022, Fall 2022, Spring 2023, Fall 2023, Spring 2024, Fall 2024, Spring 2025, Fall 2025, Spring 2026. Recorded history may be incomplete and does not establish a future schedule.

Recorded history may be incomplete and does not establish a future schedule.

Calendar & sections

Spring 2027

Schedule loads here as you scroll.

SectionModeEnrolled / capacityWaitlist
LEC 001Online Only0 / 2500
LEC 002Online Only0 / 500

Times are Central. Select a meeting for details; export includes recorded dates for the selected sections. Enrollment reflects scan time.

Meeting source records

No records available.

Student experience

the class

Past student reviews · Huifang Xu

Students described this course as an easy way to earn an A, featuring PDF lectures and quizzes that determined the final grade.

Recent recorded grades — Spring 2025: 3.45 GPA, 73.6% A/AB (n=276 letter grades); Fall 2025: 3.76 GPA, 89.7% A/AB (n=234 letter grades); Spring 2026: 3.84 GPA, 92.5% A/AB (n=280 letter grades).

difficulty & workload

Past student reviews · Huifang Xu

Exams were timed and consisted of 30 questions, requiring students to search through all lectures to find the correct answers.

Past student reviews · Huifang Xu

One student found the questions extremely nitpicky, requiring the linking of trivial details, and reported difficulty receiving timely responses regarding grading errors.

Topics

  • Gemstone formation, collection, properties, and treatment
  • Mineralogy and geological environments of gems
  • Classification of natural, enhanced, synthetic, and simulant gems

Skills

  • Recognizing common gems and their corresponding minerals in geological environments
  • Identifying factors affecting gem quality and value
  • Differentiating natural, enhanced, synthetic, and simulant gems

Grades

Historical instructor

Spring 2027 · Projected

Before grades are released

– average GPA

Approximate 80% prediction interval

About this estimate

The course’s semester-average GPA, not an individual student’s grade. The center uses 5 same-season terms, weighted toward recent results.

The range uses the finite-sample 80th-percentile rank of absolute errors from earlier same-season forecasts. Each forecast uses only records from earlier terms. At least four forecasts are required; bounds are rounded outward and limited to 0–4. This is an empirical estimate: changing instructors or grading policies can reduce its coverage.

8 earlier forecasts · 0.19 GPA average error.

Grades over time

Through Spring 2027

More grade details Grade mix, volume & source data

Where this course fits relative to

Latest available grades · Spring 2026 · all course levels

GPA

Higher than % of other courses in this group.

Course GPAs · red marks this course’s range

letter grades

More recorded grades than % of other courses in this group.

Typical course in this group: letter grades.

About this comparison

1280 courses over the same term, each with at least 30 recorded letter grades. Cross-listed courses count once. GPA is not a measure of difficulty or teaching quality. The typical course is the median by recorded grade count; tied values are not counted as lower. Grade counts describe course scale, not unique students or typical section size.

Descriptions compare GPA with this group’s average: at least 0.20 higher or lower; otherwise close to average. Section size uses median recorded enrollment: small up to 30, mid-sized 31–99, large 100+. Lectures and discussion/lab sections are described separately.

Sources & history

UW–Madison

Catalog & offerings

Descriptions, prerequisites, and recorded course offerings.

Catalog observation history

Observations at scan time; dates do not imply when a catalog change took effect.

Download part 1
Selected offering source records
GEOSCI 331 · Spring 2027

Gems: The Science Behind the Sparkle

Recorded 2026-10-14
Raw records 
[
  {
    "run_id": "20261014T203208-0851c9a1",
    "semester": "1274",
    "observed_at": "2026-10-14 17:50:09.728220+00:00",
    "offering_id": "1274:420:022130",
    "course_id": "GEOSCI 331",
    "course_uid": "course_81f4461a09a3e6c844c539a7",
    "term_id": "1274",
    "source_course_id": "022130",
    "source_subject_id": "420",
    "title": "Gems: The Science Behind the Sparkle",
    "credits_min": 1,
    "credits_max": 2,
    "typically_offered": "Fall, Spring"
  }
]
Rate My Professors

Student reviews

Original comments behind the course and instructor summaries.

Read original reviews
Download part 1
Madgrades

Grade history

Recorded grade distributions by term, section, and instructor.

Explore recorded grades
Dataset & model

Recorded 2026-10-14

View the dataset on Hugging Face
Model outputs & technical records
Qwen/Qwen3.8-27B
LLM outputs across runs
Download part 1
Full model traces

Recorded model configuration, reasoning, and tool conversations.

Download part 1Download part 2
Model & dataset provenance 
{
  "model": "Qwen/Qwen3.8-27B",
  "model_revision": "1d4bf0f2ff6012fd82039f2fa52739d0dd7c60c0",
  "task_version": "17",
  "output_id": "a184bf25ff858c7d514b4e0ff4f3f12f716ba1b4b44954dd5d2382c43cde666e",
  "requirements_status": "valid",
  "dataset_revision": "fc1811fa52e581ea57a35c0cf3343f8740a8ffbf",
  "observed_at": "2026-10-14 17:50:09.728220+00:00"
}